FAQs on Marine pH, Alkalinity 4 Related Articles: pH, Alkalinity, Marine Alkalinity, Synthetic or Natural Seawater, Water Changes/Changing, Understanding Calcium & Alkalinity, The Use of Kalkwasser by Russell Schultz, Related FAQs: Marine pH/ Alkalinity 1, Marine pH/ Alkalinity 2.  Marine pH/Alkalinity 3, Marine pH 5,  Marine pH 6,  Marine pH 7, Marine pH 8, & FAQs on: The Science of Alkalinity, Importance, Measure, Sources, Use of Additives/Buffers,  Troubleshooting/Fixing, Products by Name:  & FAQs on pH: Importance, Science, pH Measure/Test Gear, pH Controllers & pH Buffers/Buffering, pH Anomalies (Troubleshooting/Fixing), & pH Products by Name, Manufacturer, & FAQs on: The Science of Calcium & Alkalinity, Importance, Measure, Sources, Use of Additives,  Troubleshooting/Fixing, Products,

Top Off Question (5/2/2004) There is a ton of information about buffering top-off on your site, but not specifically what I am looking for.  I just got a RO/DI today, and am trying to figure out the best way to buffer my top-off water.  I use B-ionic, and thought about just using the alkalinity half to buffer (I seem to always have more of the alk part anyways).  Is this a good idea? <Seeing how theoretically the end product of an RO\DI unit should be just pure water, at a pH of 7.0, with no buffer capacity to speak of, the alkalinity buffer is a necessary additive.  However, you will probably also want to add a pH buffer to bring up the pH of the water.  You shouldn't need to add the calcium half if your tank doesn't require the extra calcium, as long as you follow the dosing instructions for the alkalinity half of the B-Ionic>  Should I buy some of that Kent Osmo-prep stuff? <I have had no personal experience with this product, but Kent marine usually makes good quality additives.  However, your current B-Ionic should work fine>  Do I just want to put a little in to get the pH moving in the right direction, or should the top-off water have the same alkalinity as the tank water? <It should preferably have a slightly higher alkalinity, and should most definitely have the same pH.  However, adding an alkalinity supplement will not directly affect your pH; unless it has other buffers as well> If I use b-ionic to buffer alkalinity for my top-off should I add less to my tank on a daily basis? <This totally depends on your system's total alkalinity.  Purchase an alkalinity test kit and monitor results to determine the correct amount of additive needed>  I could just add all my alkalinity solution for the week to my auto-top off container (a powerhead on a float switch in a 4 gal Rubbermaid container). <Once again, be sure to measure your alkalinity and dose accordingly>  I have a 55 gallon and use tropic Marin salt which I believe will mix up fine for water changes without buffering the water first.   Thanks, <No problem> -Ken <M. Maddox>

The Ups And Downs Of pH! Hi, please help with maintenance my pH. <Okay! Scott F. with you today!> Tomorrow I'm leaving my tank for two weeks... I'm quite scared because my pH isn't stable. It swings between 7.89 - 8.18 - Dangerous? <Well, remember that you will encounter day and night pH swings in most aquariums, and some fluctuation is normal.> The worst: one day the 'bottom' is 7.94, next day 7.91, and the next day 7.89. It's dropping but I don't know where is the final 'edge' - is it possible that drops to 7.80, when I will be on holidays? If yes can it be harmful? What to do? Maybe opening window will help? Water change? {today} Kalkwasser is impossible because no one can prepare it... Calcium reactor is off since last week My tank with out Kalkwasser, and reactor was able to maintain pH at the ranges 7.95 - 8.15, why can't today? <Hard to say what is causing the decline in pH...Do check your system's alkalinity, however. It's important to look at overall system conditions and husbandry procedures. Are you doing regular small water changes? Is there good circulation in the tank? etc., etc....Lots of things to review...> THANKS I know that you probably can't tell me exactly what happens here in my tank with that pH, but please tell me - should I be worried that my fish {2} and xenia will die, because pH drops to 8.7 :-(( PeterFromPoland <Well, Peter, I would not be overly concerned with relatively modest day/night pH fluctuations. You could, however, stabilize the day/night fluctuations by employing a lighted refugium with macroalgae lit on a "reverse daylight" schedule (i.e.; the macroalgae is illuminated when the main system is dark, and vice-versa...Use a more stable macroalgae, such as Chaetomorpha. I'd observe the system's overall conditions, and take appropriate actions as necessary...I would not be overly concerned about taking a vacation at this point, as long as you've done some good routine maintenance on the system, and don't see a dramatic drop in pH, have a good trip, and take corrective actions when you return. Bon Voyage! Regards, Scott F>

pH Stability 7/10/03 So, the ocean doesn't have an overnight ph drop like tanks do? <For all intents and purposes (for the specimens we keep at large), no. It is a very stable environment. There are some niches of the sea/ocean realm that are indeed somewhat to very volatile (near-shore/inter-tidal regions)... but none apply to aquarium husbandry. Anthony>

Raising pH Hey Gang, Hope it's a good day in the neighborhood where you be! <indeed bub... a beautiful day... visiting our friend Bob here in sunny San Diego> Anthony, I need to raise the PH in my tank to 8.6, I don't have a PH monitor, nor do I have all the "high tech" gadgets for dosing (reactors etc....) will SeaChem's Reef buffer be a good way to raise it, or, what over the counter product will raise ph safely, <for the dangers of maintaining an elevated pH, you really cannot do this safely without better pH testing equipment. Perhaps to high end range test kits will help> the Bryopsis <--not sure on the spelling) just will not leave my tank alone, & I'm sick of pulling it out by hand. <heavy aeration and Kalkwasser daily in small amounts to get that pH higher may do the trick> I trust you're having a great day, where ever you are in the travels of life! Thanks, Stormbringer. <with hope for you in kind my friend. Anthony>

Test Kits Hello, Maybe I have a very stupid question but here I go. I have a Saltwater test kit but now I am cycling a freshwater tank (Aquarium Pharmaceuticals). The ph, ammonia, nitrite and nitrate can be tested using the same drops and colors? Thank you, Rodrigo.<You need to make sure that the directions on the box say it works for freshwater and for saltwater. Found this link that might help you http://www.drsfostersmith.com/product/prod_Display.cfm?siteid=6&pCatId=4487 -IanB>

Revisiting pH and Xenia 6/16/03 Hello again Anthony, <cheers> I wrote to you last week regarding my declining xenia and a ph level falling below 8.3 at night.  I began dosing Kalkwasser nightly (after lights out) using your slurry method. This put the ph at a solid 8.6.  By morning however, the ph seems to be at about 8.1.   <yikes... do be careful... this is too severe of a pH swing. Have you tested (aerated a sample glass of water) to see if the tank has accumulated CO2? Much in the WWM archives on this topic> Is this an abnormally low night time drop in ph (8.6-8.1)?   <yes... severe.  .02 is more ideal> How is it still dropping below 8.3?   well insulated house facilitating accumulated CO2 perhaps. Aerate your sample glass of water outside or in a garage. The pH should not increase> I'm not sure I would want to get the ph any higher than 8.6, do you agree?  I've been doing this for five or six days now and haven't seen any improvement in the xenia. Thanks much for your help in correcting/diagnosing this problem! Bryan <small daily iodine doses instead of weekly are a nice tweak too. Kind regards, Anthony>

Is the  pH Too Low In His Tank...Or In His Mind? Thanks for the response. <My pleasure, glad to be of assistance!> Things seem to be improving. The water has cleared and PH is climbing with minimal loss (Anemone, pulsing xenia). My next question is how do I increase my ph above 8.0. I currently use Kent ProBuffer 3 times weekly but it seems to keep it at 8.0 and no higher.... Am I not using enough or do you recommend another product? < Sure, you could continue to use a buffer product. However, there are other things that you could examine here...I'd like to ask you to focus on what could be the root cause(s) of the lower pH. First, you may want to consider the time that you take your readings. Usually, the pH is at its lowest when the tank is in darkness, just before the lights kick on, and will peak later in the day when the lights have been on for some hours. When do you take your pH readings? Just a thought. Second thought- what type of regular water change schedule do you employ? I'm a vocal proponent of  small (5% of tank volume) twice-weekly water changes, as they promote stability and can keep organics from accumulating and driving down your pH. Other thoughts- do you have sufficient gas exchange and circulation within the tank? How is your feeding schedule? Do you make sure that any uneaten food is cleaned up quickly? What kind of substrate is in the tank? Finally- and most important of all- how do your fishes and animals look? If you're utilizing good husbandry practices, and everything looks good otherwise- maybe things are fine for this tank...Sometimes, we tend to get fixated on shooting for a specific value (very common with calcium), and overlook what's actually happening in the aquarium. I'm not saying to abandon testing, or that pH is irrelevant (it is not!), but do consider the big picture here. With a little digging, you may be able to find out what the factors that have been influencing your pH are, and how to correct them. Good luck! Regards, Scott F>

Raising the pH <Ola Carlos (we've just about exhausted my knowledge of Espa?l there), PF here tonight> Ok, this is not the common ask about PH, my problem is that the only salt that I can found here in my country is AZOO marine salt.  I have been using this salt more than a1 year + 2-3 months (age of my tank) the problem is that this salt only reach a 7.8-8.0 ph after diluting, I tried everything, with the water previous the mix, like aerate for 2 days, then buffer to reach 4 mEq (the PH without salt 8.5) 2 Days more, then I add salt and nothing... 7.8-8.0 the problem is not just to switch brand of salt, because there is no other brand here... In my tank the PH is 8.1-8.3 (am-pm, assume in the tank the ph raise because the use of Kalk) but I have Bryopsis and believe me is not a nutrient problem, I read that if I raise my PH around 8.3-8.6 constantly I will discourage this green algae. PH 8.1-8.3 Alkalinity 4 mEq Ammonium 0, nitrite 0, nitrate less than 5 or not detectable, calcium 350, mag 1200 Temperature 78-82?F (actually another problem but I'm working to drop to around 74-75) I will appreciate your inputs Carlos <Well Carlos, have you tried buffering with some baking soda (sodium bicarbonate) after mixing the salt water up? Try a small amount, say a teaspoon/10gallons and see if that helps buffer your water. Be careful using this with Kalk. You might have a phosphate problem, did you check for that? That Bryopsis has to be living off something. Here's the article on pest green algae's: http://www.wetwebmedia.com/greenalg.htm. Would it be possible to setup a refugium, preferably using Chaetomorpha, to compete with the Bryopsis? You might also want to try one of the bristle tooth tangs, such as the Kole Tang Ctenochaetus strigosus), they might eat it. Also, as for temperature, you might want to stabilize it around the higher end, a few degrees difference during the day is ok, but 4 is rather high (and taking it to 8 would be even worse. If you can't get it down to around 78-80, try keeping it at 80-82 instead. A little warm, but better than the constant fluctuation. Check for phosphates, and if you find them, there are materials you can use as phosphate sponges out there. Good luck beating this stuff, I've dodged the bullet so far, but known those who've had to deal with this stuff, and it's a bugger. Good evening, PF>

Pulsatory function in Xeniids- low pH 6/11/03 Hi Anthony - Upon further checking it does appear that my PH is falling too low at night.  Looks to be around 8.0 and 8.1 in the morning before lights come on.   <yikes... yes, too low for some finicky corals like Xenia sp> I'm using Seachem Marine Buffer (supposed to maintain ph at 8.3) in conjunction with baking soda. <actually... these products do not have the ability alone to raise you any higher than 8.3. Do supplement with Kalkwasser at night> I've also been keeping the sump lit (15w fluorescent light) on an alternate lighting schedule thinking that this would level out the day/night swings in ph.   <some help yes> What else can I do to keep the ph at or above 8.3 and stable? <definitely Kalkwasser dosing after the lights go off... tried and true! Archive my "Kalkwasser slurry" method here on WWM in the archives or peep it in my Book of Coral Propagation if you have access to a copy> thanks again, Bryan <best regards, Anthony>

Re: thank you 5/20/03 Thank you so much for replying and helping me :) I appreciate it so much, not many people reply when I have important questions. <always welcome, my friend> I have one more question, Corals like relatively high pH, <all marines in general favor high and stable pH especially... a steady target of 8.3 (day and night) might be a fair goal> and require so much for their growth that I couldn't begin to address it here <do focus on stability more than high-end ideals for the given ranges of chemistry and bio-minerals. Kind regards, Anthony>

Interesting pH question Bob, <Anthony Calfo in his stead. Bob travels to Hawaii this month, my friend> I almost had a fish holocaust yesterday caused by a dead Halimeda polluting my tank.   <quite possibly a vegetative act of sexual reproduction like we experience with Caulerpa (the Halimeda looked bleached and speckled afterwards yes?). This is caused by not pruning the colony adequately/often enough (allowing it to complete a life cycle) ... and/or... not doing adequate water changes and/or supplementation of biominerals (Calcium/Alkalinity) to keep up with the demand of a growing colony. Heed these needs and you can easily enjoy such algae in the future> Water turned green and cloudy and anemone turned stringy.  Fish not happy!  I removed the offender and did a massive (30%) water change and waited to hope things cleared up.  I have a refugium algae filter and live rock as my main filtering mechanisms.  Everything is clear and the fish and anemone are looking really good this morning.  Phew! <very good to hear. Water changes are life savers <G>> I have always had low ph (7.9 measured in the AM).  My hardness runs around 3-4 meq/L.   <the pH is indeed low, but the ALK is fine> Calcium before the incident was 380.   <no problem... a whisker flat. If the dosing of such minerals is inconsistent though to get these averages... that would be part of the calcareous algae problem (dosing small amounts of Calcium daily, yes?)> The Halimeda was new and the water parameters are not terrible for it, so it was probably just not a healthy specimen.   <more likely stress induced if not a lack of pruning. If not the above, then perhaps the addition of a few gallons of freshwater for evap top-off in the tank recently causing a saline differential suddenly> There is another Halimeda from the same shipment that is vibrant green--another verification of the water quality. <not a fair indicator... different stages of life cycle possible here> Anyhow, I would like the ph higher for my sanity.   <agreed> I have a nice coral substrate, but getting old.   <over 18-24 months needs some exchanging/refreshing> So I started replenishing it with new aragonite sand about a month ago.  I thought that might help with the water parameters, but the ph is still about the same.  (As an interesting side note, I used to have ridiculously high Ca as measured by my Seachem kit.  Now I figure that was due to a not very good quality saltwater mix.  I have switched to Instant Ocean.) <very good... agreed with the move> I thought with this large water change that the ph might budge higher a little.  It didn't.  I had to make up new saltwater yesterday after doing all of these water changes.  After testing the tank ph this morning, I ran out to my garage and tested the pH of the water that has now been heating and mixing in my trusty Rubbermaid for almost 24 hours.  It measured 7.8!!  I'd like to fix the pH of my synthetic saltwater before I even think of tackling the pH in the tank. I use tap water that is pretty hard.  I fill the container, add my salt and Amquel and allow it to mix with a powerhead and heat for about a week with the lid on the barrel to prevent evaporation before using.  This lasts me several water changes usually.  I don't usually test the ph, figuring the synthetic salt should take care of this.   <agreed/largely> Could the lid on the container been preventing gas exchange, keeping the ph down? <in any vessel yes... but what of the display tanks low pH? Test any/all by aerating a glass of saltwater outside for 6-12 hours and seeing if you get any pH increase> What should be the procedure?  Should I buffer it with baking soda prior to adding the salt?   <depends on the pH/hardness of the freshwater you are using> If I keep the lid slightly open, don't I then have to worry about salinity due to evaporation? <very little concern here... do encourage good gas exchange> I don't usually do any Kalkwasser dosing or anything.  I do have a Kent 2-part calcium  buffer around when from when I first set up the refugium and the Ecosystem folks said that I might have to dose calcium with this set up.  I got it just in case, but haven't really used it. <I would strongly encourage Kalkwasser use... and strongly discourage any liquid calcium (chloride) long term usage [much info in our archives and out on the 'Net about the dangers of using liquid calcium long term... problems often after a good 8 months or more]> Thanks again for all of your help.  You have made my aquarium hobby much more enjoyable. Linda <with kind regards, Anthony>

Re: Interesting pH question 5/19/03 Also forgot to mention maybe that the saltwater mix barrel is in my garage which is a VERY loose design, virtually outside with open vents and dog door with no flap all over the place.  Only the sometime presence of my dog keeps the critter population down! I once tested the hardness of the tap water here and it was fairly hard and the website of the source water company says it is 145-204 mg/l. The pH is listed at 8.1-8.3.  So now I am suspecting a bum pH test kit. As a quick science experiment, I double-checked with a Hagen high range pH kit that I have lying around, not expired yet (hard to read accurately, so I bought the Seachem at some point).  The source water out of the tap is indeed 8.1-8.2 and the water in my barrel is still reading very low, about the same as the other kit, maybe as low as 7.6 but hard to read especially at night.  I don't understand what is causing the pH to drop in just mixing the saltwater up.  I am not a chemist but have studied some chemistry and this makes no sense to me at all with no bioload or anything, unless I got a bad batch of salt... <a bad batch of salt is highly unlikely. Do check out chemist Randy Holmes-Farley at reefcentral.com (he has his own forum there). Great chap and perhaps can lend insight. Kind regards, Anthony>

Re: Interesting pH question 5/20/03 an update: Okay--The pH in my tank is not as bad as I thought. It is about 8.1 at the end of the day (11 hours after lights on). <okey-dokey :) > I realized that if the air stone raised the pH in the glass of water (I did finally get to this experiment, and it worked), it would do the same for the barrel of water. So, I introduced the air stone and 5 hours later the pH in the barrel is 8.1 also. <ahhh, very good> I wonder where the CO2 is coming from. <common in well-insulated modern homes/apartments with weak air flow inside> Maybe I need to really rinse out the saltwater barrel next time it is empty to make sure that bacteria aren't getting the best of it. <not the bacteria at all IMO... but do rinse well to prevent skewed residual bio-minerals/precipitates> I am going to start dosing a little Kalkwasser for the sake of the live rock and Halimeda. <agreed, my friend... excellent to hear> Thanks for all of your help. <always welcome :) > Randy [Holmes-Farley at reefcentral.com] was a great resource too.  I highly recommend the articles on that site. Linda <agreed again... Randy is a brilliant and no-nonsense chap... I defer to his skills/discipline. With kind regards, Anthony>

Fluctuating pH Levels... Clarification on a couple of points if you don't mind.  Why would the ph be lower at lights out and higher when they first come on in the AM? My understanding was it should be the other way around. <Actually, you're right. My fatigued eyes misread and reversed your numbers! The general fluctuation is downward during the dark periods, and up during lighted intervals. The highest pH of the day is usually just before "lights out". Photosynthetic organisms (like algae) will remove carbon dioxide during the day, and expel it at night, which causes the decline in pH during the dark hours. Removal of C02 by photosynthesis results in the production of less carbonic acid, thus raising the pH. It may be that you have low carbonate hardness and alkalinity, which may result in this unusual reversal of the dynamic...I'm just postulating here. Do check alkalinity and carbonate hardness...> The reason I asked if I can dose Kalk twice per day (one teaspoon in the AM and half a teaspoon in the PM) is because I cannot dose the whole amount at once because the ph jumps up by about .25.  Is this acceptable, if not I will have keep dosing calcium in addition to the Kalk.  Thanks again. <Well, I  agree with you about not wanting to fluctuate the pH too much. I generally would avoid a correction of more than two tenths of a point in a short duration. Frankly, I'd strive for consistency over anything else here. Some people (myself included) help maintain a stable pH in their systems by growing macroalgae in a lighted sump beneath the display, operating on either a continuous basis (25/7/365), or a "reverse daylight" method. It does work, so you may want to check out this concept. Sorry for the initial confusion on your pH. Hope this helps!

Where can I get buffers for calibration? I've received an electronic pH tester, but it didn't come with calibration buffer... I need a buffer with pH or 7.01 and then either 4.01 or 10.01 to calibrate it. Where can I buy this (or what can I use?) thank you, Luke <Mmm, I would buy such "standards"... either from/through the industry (try Marine Depot or Custom Aquatic... links on WWM, or through a chemical supply biz on-line. Use your search engine and the term "pH standard solutions". Bob Fenner>

High Ph other general questions >Hello, >>Good morning, Kevin, Marina here. >I currently have a 50 gallon FOWLR tank that has high pH levels, 8.4-8.6 what is the best procedure for getting back down to 8.2?  Would doing a water change with fresh water fix this?   >>First things first, do you know what may be causing a wide swing?  8.4 isn't so bad, 8.6 is a bit high, but if the specimens look happy, I prefer not to play with the pH. >Also my salinity is considerably lower than usual 1.019-1.020.  I'm guilty of the lowered salinity, when I change my foam filter media I have been refilling the filter's with fresh water, would this also be the cause of the high pH? >>Only if the freshwater has such a high pH.  Otherwise, generally, no. >Last question ;) I promise, when doing water changes is it advisable to add the salt at the time of the change or would you mix it ahead of time?   >>ALWAYS premix the salt, and have it circulating *before* you make your change.  Also, I suggest testing both the water used to mix the salt for pH, and then test the water once mixed before it goes into the tank.  See what you get there.  If it's in the acceptable range (under 8.6) then I usually use water changes to get things back in order SLOWLY.  Messing about with the pH can kill VERY quickly, and if the water is very buffered, you'll have a devil of a time getting it stabilized where you want it.  Again, if everything appears alright, let it be. >I have been on a two week water change schedule and have been mixing the salt into the water and letting it sit for two weeks with a heater and an airstone, would this be proper procedure, am I doing something incorrectly? >>Two weeks is a bit long, 24hrs is acceptable, using the airstone to mix and keep aerated is great, heating is also best (we don't want temp shocks).  Best of luck!  Marina

- Can't lower pH - Help...... <JasonC here... I will try.> I can't seem to lower the pH in my 90 gallon Reef tank.  I have tried several water changes over the last few weeks, but nothing has helped.  I have tested my mixed saltwater and it is at 8.2 I did a 30 gallon water change and tested the tank early the next morning and the PH is still 8.4 or higher. <I'm not sure what 'or higher' means, but 8.4 is perfectly acceptable.> It seems like this all started when I added Aragamilk to my system. <Hmmm... does that mean you've stopped adding it?> Some of my corals have died and a couple have just shutdown. I have lost most of my inverts and my Sand Sifting Starfish looked like something was eating parts of his legs and finally he died as well. <I'm sorry to hear this.> Could there be something in the tank that could be causing the high PH? <You would know better than I - what have you been putting in there?> Setup: 90g Bow Front W/ 110-120 pounds Live Rock Oceanic 150 Sump W/ Live Rock 3 1200 Maxi Power Heads 1 Yellow Tang 1 Yellow eye Tang 5 Green Chromis 1 Clown 1 Coral Beauty 1 Purple Starfish 1 Seastar? <Cheers, J -- >

- Daily pH Fluctuations - Dear WWM crew <Good morning, JasonC here...> Back again with a shorter question this time. My PH used to be 8-3 , 8,4. Since the last addition of some fishes it has dropped to 8-15 , 8-20. I guess that is normal for a still young tank ( 5 months old). Problem is that during night PH falls to 7-98 and as soon as the lights turn on it rises again to the normal levels. Is that a normal fluctuation or should I do something about it? <Well... I noticed you have a calcium reactor in the mix there... you might consider putting the solenoid on the same timer as your lights - that would help.> (I have SeaChem Marine PH) I haven't used it so far. <You may also want to consider, if you don't have it already - and you should with that reactor there - an alkalinity test, perhaps your reactor needs adjustment.> tank 150 Gallons Calcium reactor. Some weekly additions of Seachem Iodine. Otherwise feeding normal, phytoplankton and flake food. Best Regards Kostas <Cheers, J -- >

pH drop at Night My PH has been dropping radically at night.  When I check it first thing early in the morning, it is dangerously low. <Not unusual to drop to 7.9 or so in some aquaria.>  Lost a flourishing xenia colony which I attribute to this phenomenon. <Perhaps, but could be several other factors. Xenia does well in some tanks and not in others, depending on light, nutrient, iodide, etc. IE: my Xenia tank drops at night and I couldn't stop the stuff if I tried. You still may want to remedy, several choices here.> I have been dosing with two part bionic and nothing else.  What do you think of the idea of dripping the buffer slowly during the evening and then adding the calcium later in  the morning ? Thanks in advance for your help. William Snyder Stuart, FL <You can do this. I suggest testing alk and calcium regularly with two parters to make sure all is as expected.  You could also drip Kalkwasser at night (follow directions on B-ionic label for dosing with Kalk) to stabilize pH. I also suggest a pH meter to monitor pH and adjust Kalk dose.  Also refugiums on an opposing light cycle will stabilize CO2 content and thus, pH.  Good luck!  Craig>

More on High pH Hello, >Sorry hon., no time for greetings.   Get enough water to do at least two 50% water changes.  Do 50% first, then test.  Try to siphon all micro algal (or Cyano) growth you can, there's a huge influx of nutrients and you need to get it sorted out ASAP. It's been a while since I have needed your advice, and this time it's somewhat of an emergency. I was out of town for a few days and my husband turned of the light to my refugium for what must have been at least 48 hours or so straight.  This resulted in a Caulerpa crash (I just found all of the information about how bad Caulerpa is in the first place). >It's not bad for nutrient export, just in environs where it doesn't belong. So I removed the Caulerpa which served as a breeding ground and food for a bunch of critters (to feed a mandarin).  In the past day, I've had death among my inverts, cleaner shrimp, serpent star and a least one snail.  Also in the past day, red algae (looks like diatoms, not slime, although I have one little patch of the slime starting).  Also, green star polyps not looking good today (just not out very much).  And the whole tank has this really eerie look to it. Tested what I could with my kit at home (0 ammonia, 0 nitrates, 8.8 ph!!!).  So, my ph is way out of whack.  WHAT should I do first, at all, etc.  I feel like I need to jump on this situation in the next couple of hours, and I stand ready to head to the store for whatever you tell me I need. >Water changes are going to be your best weapon at this time.  They will help bring the pH back into whack, I wouldn't fiddle with it at all right now. Other inhabitants include some Ricordea, mushrooms, brittle star (unless he's dead, too), hermits, snails, mandarin, Banggai pair, bicolor blenny and a couple of other soft corals. Let me know what other information I can provide that may be helpful.  System is 2 years old, never had another problem.  75-gallon reef with 10-gallon refugium.  Protein skimmer and Penguin 330 for mechanical filtration.  5-6" sand bed.  100+ pounds of live rock. Kind regards, Misty >Ok girl!  Get on it, and we'll move on from there!  Marina

Creep(ing) pH (04/03/03) Greetings, <And salutations...Ananda here tonight.> I have a 45 gal  high, (5 gal sump). Water parameters are great (SG 1.205, Nitrite 0, Nitrate 2) and everything looks great, including the two PJ cardinals, 1 mandarin, 1 Firefish,  1 banded coral shrimp and various soft corals and Tridacna.  My concern is the slowly upward-creeping pH.  I bought the pH meter about 2 months ago, calibrated it and found that the pH was about 8.25 at its highest during the day, falling to 8.00 by morning.  Over the course of the last two months, I started increasing the pH slowly using Reef Buffer.  Now, I notice that the pH will go as high as 8.60 during the day, and fall to about 8.30 by morning.  Is my pH too high at 8.60?  The Ca is 380. <The pH at 8.6 is pretty much at the upper end of the allowable range. If you want to decrease the daily variation, you might try adding a refugium on a reverse lighting cycle. More info on the WetWebMedia site... try out the Google search tool at the bottom of the main page, looking for ''pH swing'' and ''refugium''....> thanks tom <You're welcome. --Ananda>

Help, High pH, Crash Soon? (04/03/03) Hello, <Hi! Ananda here this afternoon.> It's been a while since I have needed your advice, and this time it's somewhat of an emergency. <I'll throw my few pence in and let someone else comment, too...> I was out of town for a few days and my husband turned of the light to my refugium for what must have been at least 48 hours or so straight. <Oops. You'll want to get a timer for the refugium light.> This resulted in a Caulerpa crash (I just found all of the information about how bad Caulerpa is in the first place). <I like Chaetomorpha much better. So do the pods.> So I removed the Caulerpa which served as a breeding ground and food for a bunch of critters to feed a mandarin).  In the past day, I've had death among my inverts. cleaner shrimp, serpent star and a least one snail.   <My sympathies...but you still have the fish, yes?> Also in the past day, red algae (looks like diatoms, not slime, although I have one little patch of the slime starting).  Also, green star polyps not looking good today (just not out very much).  And the whole tank has this really eerie look to it. <Water change time....> Tested what I could with my kit at home (0 ammonia, 0 nitrates, 8.8 ph!!!).  So, my ph is way out of whack.  WHAT should I do first, at all, etc.  I feel like I need to jump on this situation in the next couple of hours, and I stand ready to head to the store for whatever you tell me I need. <Nothing new, unless you're out of salt or something. Seriously. What you need is a water change. You do NOT want the pH to swing quickly! Don't lower the pH more than 0.2 points in 24 hours. It took two days for the pH to get this high; it should take at least that to get it back down to around 8.3.> Other inhabitants include some Ricordea, mushrooms, Brittlestar (unless he's dead, too), hermits, snails, mandarin, Banggai pair, bicolor blenny and a couple of other soft corals. Let me know what other information I can provide that may be helpful. System is 2 years old, never had another problem.  75-gallon reef with 10-gallon refugium.  Protein skimmer and Penguin 330 for mechanical filtration.  5-6" sandbed.  100+ pounds of live rock. <Sounds like you have all the info bases covered... Now, imagine a sign in nice friendly letters: Don't Panic. Your tank will recover from this. --Ananda> Kind regards, Misty

Re: Help, high ph, crash soon? (04/03/03) Ananda, <Hi again.> Thank you so much...should I do a "slow" water change to avoid the ph swing?  I usually do at least 10%...would it help to do 10% twice over the next two days? <That might be a good start. It depends on the pH of your replacement water. To find out how much you can safely do, you need to do a bit of math... In the equation below, new-water is the percent water change you want to do; old-water is the percent of water you are keeping. Both are expressed as decimal values; i.e., 20% would be 0.2, so new-water = 1- old-water... (new-water pH * new-water ) + (old-water pH * old-water) = new pH > Also, will this help get rid of the red algae, or do I need anything for that?   <Ah. You need to get rid of the algae's food sources: nitrates and phosphates. You might consider investing in a phosphate test. I have phosphates in my source water, so I use two phosphate tests: the SeaTest kit for the "high-range" phosphates, and the Seachem test for "low-range" phosphates. There's a *lot* more info about algae control on the WetWebMedia site.> Final question...should I suspend feeding for a couple of days? <In combination with the water changes, it might help reduce the phosphates and nitrates a bit, but isn't 100% necessary.> I'm breathing a little easier...not much, but a little. <Hang in there -- we don't want to have to send over the paramedics with the oxygen.... --Ananda> Kind regards, Misty

Re: Help, high ph, crash soon? >Hello WWM crew, >>Hi Misty.  Marina again for you. >I did a 12-gallon water change today (5 in the afternoon, another 7 a few hours later).  pH still hanging in right around 8.4-8.6 (hard to tell on those tests sometimes).  Snails still mobile, hermits out and about as well.  I gave the fish a 1/2-meal tonight and they snapped it up quickly. >>Good, I think you've acted quickly enough and things should be getting back to normal soon enough.  A pH of 8.4 is good.  Even 8.6 isn't too terribly bad, you're out of the danger zone. >I will test again in the a.m. and do another 5-10 tomorrow night depending on the test.  I do have a concern about my bicolor blenny.  He seems to have a white area on his tail...could he have gotten a pH "burn" or something like that?   >>I've personally not seen pH affect a fish quite like that, but the stress at least certainly could have caused a wee bit of trouble. >It's not hanging off of him or anything like a fungus would.  And it's not spotted like ich.  I've got to think it's related to the high pH condition.  Any specific treatment, ideas, etc.?   >>Not just the high pH, but the excess nutrient dump when the Caulerpa died off.  If he's behaving normally, eating and all that, then I will just suggest having a hospital tank ready for him should he show further signs of illness.  Also, have either Spectrogram or Melafix on hand, just in case.  In the meantime, begin feeding normally, if you don't use supplements then give him (and all the others) that little extra boost.   >I'm a little attached to him, as I bought him the afternoon of 9/11/01 (had to do something that felt normal so it was comforting to talk to my LFS friends and have a little one to take care of that night). >>Clearly understood.  We all lost that day. >Seeing a little hair algae now as well, not a ton.  Also some green algae on the glass that isn't hair algae (bright green, scrapes off easily).  All of this sounding normal for what has happened? >>To be expected, I think with the additional water changes your only problem will be re-establishing the nutrient export that the Caulerpa effected for you. >Thanks for the help, advice, encouragement, sanity-check, etc :-) Misty   >>You're quite welcome, I'm *very* glad that your only losses were the Caulerpa.  Keep us posted!  Marina

Help, high ph, crash soon? >Marina and crew, >>Hi, Misty.   >I did a 10-gallon water change and my ph went from 8.8 to 8.6.   >>That is FAR more acceptable.   >Snails started moving again, as did my Sally Lightfoot.  I didn't want to do anymore, as I'm not supposed to move the ph more than .2 in a 24-hour period, right?   >>Generally, yes.  However, there arise certain situations where it's far better to get the specimens in question back into water that is more acceptable quality-wise.  However, 8.6 is indeed far more acceptable, so unless you see more signs of stress you can go it more slowly.  I would do another water change today, though. >If I do a 50% water change all at once, won't that lower the ph too quickly? >>Again, generally yes, but you can also do what's done in shipping.  You can do an exchange drip, so that the change isn't so sudden.  You would make a drip line going out of the tank, and make one going *in* to the tank that's dripping at the same rate.  Problem solved. >Should I put in a new carbon filter in the Penguin 330, and maybe an extra carbon pad or something?   >>That is not a bad idea, and I don't see it hurting at all. >I've already turned up my protein skimmer to full blast. >>Good move. >I siphoned out what I could, but there isn't that much yet, and it's not the kind that usually settles on the sandbed.  I also have a type of red feather-looking macro...will that help any? >>Yes, in fact, it may have been the macro that has helped "mop up" some of the nutrients that were released with the Caulerpa die-off.  So, just do at least one more water change, test again, and watch closely.   >Thanks, Misty >>You're welcome, and keep us posted.  Marina

Re: Help, high ph, crash soon? >Hi Marina, >>Hi Misty. >Did another 2.5-gallon water change (just what I had left from last night).  Took a water sample to the store for testing to confirm my pH test and to look at phosphates. >>Great. >pH was 8.5.  Phosphates read zero, but the guy said that it wasn't a very good test.  Came home, did another 5-gallon change tonight.  Will do another 5 before bed and another 5 tomorrow. >>Sounds like a prudent course of action, and I think you're out of the danger zone. >Fish are still very active and eating, snails and crabs "alert" as well.  Blenny is acting normal, and his tail looks a little better.  I do have Melafix on hand just in case. >>Very good, I think that with the additional water changes planned you'll soon be golden. >If the pH spikes up again, I'll let you know.  Otherwise I'll keep on my road of 5-gallons a day until things stabilize. >>Excellent plan. >Thanks again for all of your help with this minor panic. >>Minor my foot!  A pH change as you described along with that mass die-off of the Caulerpa could have become a major disaster *very* quickly. >Kind regards, Misty >>Very welcome, and VERY glad to hear that all residents are well.  Marina PS...If nothing else, all of this has gotten me looking at a reef ready 115 at the LFS!!!  This hobby is really sick sometimes...talk about being a glutton for punishment! :-)  

Re: Help, high ph, crash soon? >Marina, >>Misty?  (I wait with baited breath..) >8.2, sweet 8.2!!!  And an extra 10 gallons on hand just in case! >>AAAAHH!!!  So sweet is the proper pH.  How's that blenny, too? >:-)Misty >>Let the relief and happiness ensue!  Marina

Re: Help, high ph, crash soon? >Hi Marina, >>Good morning Misty. >Everything still looking good.  Blenny's tail just has one little spot of the white patch left (very tiny), so I think he's on the mend.  Thanks again! Misty >>You are MOST welcome, the cockles of my heart are warmed to know of the disaster averted.  Marina

All Tangled Up! I have 125 gal with 3 regal tangs.  For the past couple of weeks two have them will stay hidden, the third comes out but it is very skittish.  I have added nothing new to my tank.  Any reasons for this change in behavior?  I have recently experienced a drop in pH.  They don't look sick.  Could this be breeding behavior? <Bingo! pH drops are stressful events. Anthony gives the analogy that a pH drop of several points is something like being transported instantly from a tropical beach to the Arctic (while naked!). It is a good one, too! You may survive, but the stress would be amazing! So, my best advice to you is to find the cause of the pH drop, and take corrective actions to stabilize it, and, more important-to prevent it from happening again. These kinds of drops are usually caused by a lapse in maintenance, possible overcrowding, or other, quite "correctable" things. I'll bet if you correct the problem, you'll see those tangs perk up nicely. Look for the cause, then affect the "cure". Let us know if you have any additional questions! Regards, Scott F>

pH and Temperature Dear Crew: <Hi Eric, Don today> Is there a difference between pH of water due to difference in temperature?? <Not that I am aware of> Can differences in water temperature affects the reading of the pH meter?? <As above> Eric

pH and dKH My 90 gallon tank with 90lbs live rock has a ph of 8.6 and dKH of 14.5. Do you see any problems here and what should I do if there is? Thanks <No, no problem, however, don't add anymore carbonate/buffer supplement! Don't attempt to hold both alk and calcium in this high range. 14.5 dKH is 5.17 meq/L alk.  For those trying to figure it out, dKH is meq/L X 2.8.  Normal range is 9.8 dKH to 14 dKH.  Not to worry about either, esp. if 8.6 pH is in PM. If this were accidentally too high, you would perform water changes to lower alk to normal levels.  Hope this helps!  Craig>

Re: water pH values/ Dear Crew: I am having trouble understanding pH fluctuations. First of all, I have trouble keeping up pH in my system, and I started to think what has happened.  I normally change 15-20 gallons of water every week in my 125 gallon reef tank. It is not heavy populated (I have 2 finger coral, and 1 big devil hand, plus some polyp, 3 cleaner shrimp). that's it.  My alk is good. 3.6meq, but my pH is low 8.2's. never achieve 8.3. <This isn't a big problem.  Your alk is on the bottom of normal. Nominal range is between 3.5 - 5 meq/L.  Adding balanced marine buffer or carbonate alkalinity supplement will raise alk and pH.> Possible problem includes measurement error and instrument. I measure the pH using my pH meter, and I use the same meter to measure all things, so it has no relative error, at least this is not what I have been worrying about, I started to measure the freshwater that use to make up my saltwater. <Doesn't sound like meter.> The freshwater is about 7.92 and when stored in a Rubbermaid container, no light and aerated for 1 day, it is 8.12. and when aerate for 3-4 days, it is 8.5-8.6!! Then, I use this water to mix the salt (instant ocean) and measure the seawater, the seawater is 8.00-8.02!!! what is wrong??? <Sounds like you are using tap or well water without RO or DI. Your tap water contains hardness elements that are registering on your pH measurements, also would on total alk tests if you did that. There is some kind of cross-reaction happening with your water from it's contents (likely calcium, magnesium, manganese, etc.)  When you aerate you balance oxygen/carbon dioxide and raise pH.  Are you aerating your salt water before measuring pH as you are for top off?  The same thing is happening with your salt mix as is with bicarbonate (which I do not recommend, use a good marine buffer) bicarbonate and carbonates in the salt buffer are being sequestered or reacting with your water contents.  I would use RO water to remove the problem.  I would bet your tap water has calcium, magnesium, manganese, etc. that sequester/react/depress carbonates you are adding in bicarbonate or salt and contributing to pH issue (which is very minor).> My QT water is very stable, having no substrate it is always 8.25. but my reef tank never can achieve above 8.2!!!. <No mineral content in substrate to react with, depress pH/alk. >   Another problem with my main tank is I cannot upkeep calcium levels... although I change water very frequently, and my tank is not heavily pop, ca is very low (260ppm)... but my corals and coralline are fine, and open up beautifully!!! I am greatly confused.....<Yes, I can see why.> Last problem is that my water go low pH when baking soda is added. why? Eric <I recommend testing your tap water to see what it contains that is doing this. Try using RO/DI water (perhaps from LFS at first) to see what happens when you start with pure water without conflicting elements. Aerate as you have been and see what it tests out as. I would also suggest getting calcium up to about 380-400 with a good supplement and perhaps think of using Kalkwasser for calcium and pushing pH a hair when you figure out your mineral issue.  Hope this helps!  Craig>

pH and Kalkwasser Hi Bob, <Hello Karl, Craig here today.> Before I start, I would like to thank you for offering this service/site. It has been an invaluable source of information for me whilst I try and learn the tricks and methods of marine husbandry.  I have read most of the Marine information on WetWebMedia, and my only wish is that the people at my LFS could offer the same standard of information that WetWebMedia do. <Thank you, it's our pleasure!> Let me begin, The Tank is about 8-9 months old. Spg 1024 Temp 25-26.5 pH 7.9 - 8.2 (Red Sea) KH 9 (but cannot keep it @ this - Aquarium Pharm) Ca 385ppm (Salifert) Mg Approx 1250ppm (Salifert) PO4 < 0.25 mg/L (Hagen - lousy test kit) Ammonia 0 Nitrite     0 Nitrate      < 5ppm Tank: 30gal (36" X 12" X 16") Filtration & Circulation: Eheim 2213 Canister Filter running RowaPhos every 2 weeks and PolyFilter every other 2 weeks Seaclone Skimmer (drat! should have read WetWebMedia before hand) produces 1/2 a cup every week (terrible!) x3 Eheim 150gph powerheads for circulation Lighting: x4 NO Fluorescents in rain gutter hood with reflectors (10 hours a day) Livestock: x2 Small Colonies of Metallic Green Star Polyps X1 Semi-Large Devils Finger X1 Dying Pulsing Xenia X1 Midas Blenny X1 Peppermint Shrimp X5 Blue Legged Hermit Crabs X10 Snails <Right off, do increase photoperiod to 12 hours per day. Low light is part of problem with Xenia along with short photoperiod. This may temporarily increase algae, but will actually push it along to depleting nutrient, thus algae over time.> The first problem I have is: I cannot seem to keep my ALK levels where I want them.  I am aiming for 11-12KH, but can't even get to 10.  If I do, it will stay there for a day and then drop down to 9 or less.  I have tried C-Balance however that seems to raise my Ca alright but only raises my ALK for a day or so and then it goes back down. <Yes, these need to be added at separate times (AM/PM) or alternate days. Calcium will depress alk and vice-versa. Calcium is at the bottom of the nominal level and alk is also (actually a hair below the lowest I would like to see. This is not uncommon with the "balanced" two part supplements. You may need to increase dose or switch to a better supplement regime.> Last night a I tried out Seachem ReefBuilder.  I added 1 teaspoon and that raised ALK from 8 to > 9 and drop the Ca from Approx 400ppm to 385ppm (as it should do ?). <Yes, this is normal/expected. I would also use Seachem Reef Builder (raises alk .5 meq/L (1.4 dKH) per tsp per 40 gallons) or Seachem Marine Buffer which will raise carbonate alk 1 meq/L (2.8 dKH) per tsp. per 40 gallons. I use both of these products along with Kalkwasser and periodic magnesium supplementation with Seachem magnesium according to use/test. I use Seachem tests, Salifert is also good. Do use the best kits you can afford. You may also wish to use the C-balance at a higher dose along with the Seachem products to maintain alk as needed. Calcium and alk on different days.> The levels I want to attain are 11KH and Ca 400ppm.  Are these reasonable ? <Yes, I prefer higher alk (11-12 is a good range) with 400 calcium. Both at high levels is trouble waiting to happen. Moderate on both with adequate testing is best.> My LFS told me something is using the ALK probably coralline algae (can't really believe this as I don't have very much of it only hair algae / Cyano). <Depends on system dynamics, inhabitants. This is not unusual in my experience.> I am trying to hit these levels as I read problem algae do not like these parameters.  I have had problem algae on/off for about 5 months (hair and Cyano).  I change about 3gal of water a week using methods described on WetWebMedia (i.e. aerate 1 day etc..) <Yes, this will help, as will checking alk and calcium on new water. Add buffer/alk as needed to new water after aeration, etc.> Do you think I should dose with ReefBuilder and then raise the Ca by adding equal parts of C-Balance ? <You can use the Seachem to raise alk as needed, then use C-balance in equal parts added at separate times as above. Increase dose to raise calcium to 400. One separate day raise alk portion of C-balance and SeaChem to raise and maintain alk at approximately 12 dKH.  Get the alk up first, it is low presently.> The second question a I have is regarding Kalkwasser I want to start using this due to it's benefits (precip phosphate, increasing pH and support ALK). Do you recommend dripping this into the skimmer column ?   <Better into the display at night/early AM to maintain pH at night. You will still need to supplement alk with Seachem Marine Buffer and/or Reef Builder. Both excellent products for your application. I *know* you will read more on WetWebMedia on Kalkwasser use!> Thanks again in advance. Karl McNally (from the UK) <All of our best to you Karl.  Enjoy!  Craig>

Re: pH - top off water Cody, That link I've read many times. If you would be so kind as to re-read my email and try to respond to the question concerning the use of regular baking soda...and the maximum pH level baking soda will create, and approximate addition (tablespoons) per 20 gallons to max out the pH at that magical saturation level (whatever it is for baking soda...I think 8.2 ??) <Sorry about that Steve.  You were correct about baking soda only raising the PH to 8.2.  After it does get to 8.2 it starts to decline.  There is no set amount you should add as it all depends on the source water.  Just slowly add small amounts until you get to the desired level.  Best regards, Cody.> Re: Low Ph Since asking the questions I have since been adding Kent SuperBuffer dKH. My kH value before which I did not say was 5.8 on the Salifert test and now after three days of testing and adding buffer it has rose to 9.3 kH, but my ph rose only slightly to 6.41. What gives? Buffer should adjust the ph right? Should I continue to add till the kH value is 11 and see if my ph rises accordingly? <What is magnesium? All else being normal I would suspect low magnesium with Kalk use.> I live in a 100 year old farm house and have a large venturi skimmer so the aeration does not play a role in this. I have 30 gallons of water that is testing 6.8 and a sal of 1.022. I don't get it shouldn't the Kent salt mix give me the 8.3 ph value I desire? <Not with RO/DI water starting at 5-6 pH! Most salt mixes don't account for this and require testing and sometimes buffer, calcium and in some mixes, magnesium. Well water also requires 12-24 hour aeration before mixing w/salt to help equalize to reveal true pH.> The pinpoint has been a couple of months since re calibrated but while in water for 7 months constantly, I would turn on every few days and the reading was 8.0-8.3.  Then tested calk water (12ph) to see if I could reuse the Kalkwasser that was left in the bottom, and then I put back in sump and the reading was 6.3ph. <I think it's your probe.  Check it against a colorimetric test like Salifert or SeaChem.  Also connections at meter and line.> I am beginning to believe I have wasted your time asking questions  as I write this due to the fact that calk water can't change from 12ph to 5.8 in the same mix can it? Unlikely, more likely the probe. Should the Kalk keep my alk/ kH levels high or do you still need to buffer once every few weeks. Thanks again Shawn. <You will likely need to add a carbonate supplement/buffer according to testing and also magnesium according to testing/use to maintain proper alkalinity and pH with Kalkwasser use.  I would determine use and supplement regularly, testing at least every two weeks to make sure you are within norms.  Craig> Just a few things to check!  Craig>

Low pH I have been adding Kent marine Kalkwasser for ever but in the last month or so have been dosing 5 gal a day to a 240gal total water vol system to lower salinity, well it turns out that I in turn dropped my ph to a scary 6.5. I use the pinpoint ph which obviously needed some calibrating. Did this and checked my calk make up water and it was around 12dkh which I thought was great and later I just by chance checked the last 2gal left and it was a whopping 5.6 what gives? <How old is your pH probe? I would check it against an accurate  colorimetric test. I can't see how your Kalk water would be 5.6.> My water is well water and is around 5.3 but have had no problems that I was aware of until now. Kent marine 60max hi-s is used for purification. It measures 5.3. Should I get RO right maybe? <You make no mention of alk/carbonate, and I'll bet it is rock bottom and perhaps magnesium as well, as your water change water seems right. It has the full compliment of magnesium etc. from new salt... Carbonate/alk should be 3.5-5 meq/L (10-12 dKH) and magnesium three times calcium (1300 +/-). Kalkwasser will deplete magnesium and you need to supplement or at least check carbonate/alk every two weeks or determine usage and supplement to make-up use. Test magnesium and alk weekly along with calcium to make sure Kalk is enough.  It generally isn't enough to make up carbonate alk.> Water changes seem to measure out correctly.  The corals are thriving and the fish are doing well. I recently added 4 - 48" day light bulbs over the 150gal sump on an opposite cycle as the tank to get more room for macro algae. I have had a lack of macro growth in the 30gal miracle mud filter here in the last few months could this be due to my dropping ph? <Likely, pH is important to plant growth (photosynthesis in corals and plants).> I mean there is new growth but not what I was used to seeing over the past year. By adding these lights over the big sump I have had a outbreak in slime red and green algae, while the macro seedlings are growing they are not shooting up at any alarming rate. <Likely due to poor water params.> The 135 display tank is algae free and fully coralline encrusted which blows my mind after looking at the sump. Maybe a pair of purple tangs and a Chevy are that good huh? Need some good advise before a disaster on my hands? Sal 1.025, nitrate 3ppm, cal400-430. Help?? <Test magnesium, carbonate alkalinity, lower nitrate/raise magnesium and alk with water changes (I would test new water, you will be surprised at moderate to low mag/alk/calcium in new water) and supplement new water with needed elements, esp. starting at 5.3 out of the RO.  Aerate 12-24 hours with salt, check alk/ph and add buffer as needed. These are notoriously low on alk/calcium and some low on magnesium, all contribute to depressed pH. Think about replacing the pH probe, they last about 18 months of continuous use. It could be on the way out....  Hope this get's you back in the ballpark!  Craig>

pH problem I have had a problem since I moved into my new house (it's been over 2 years) with green hair algae and now the red slime. I neglected water changes for almost a year, as the tank was healthy, so I left it alone. Once I did a couple of water changes I started running into the problem with the algae. We have tested the local water, but all is well, WELL within limits. <Test for Iron, Silicates and a nitrate of 10 isn't low or within limits, start there. It's either source water or accumulated wastes from lack of new water. I would do a massive water change after blasting everything with a powerhead/baster and vacuuming the gunk out.  Also kick the skimmer in the pants, give it a cleaning/adjustment and get it skimming as it should or replace it.> As for the aquarium water, my phosphates are almost non-detectable, by nitrate is probably around 10 and my PH was at about 7.8 until I used Seachem SuperBuffer DKH to bring it up to 8.3 (or so). <Normal enough. I would lower the nitrates.> I did so in order to try to make some change that the algae would not like - I'm pulling my hair out trying to get a handle on the algae issue... <Get a handle on wastes and maintenance and the algae will come along.> I had the lights (CF's) set for around 10 hours a day, so to try to knock down some of the algae I cut the feedings to once a day (sometimes less - and I hate doing that, too... I know there's a better way), <Yep, export, skimming, water changes, etc.> and knocked the lights down to around 4 hours <Tell me this is fish only.....If so fine. If not, better turn the lights on 12 hours. Using the lights will *speed* the use of nutrient by the algae and cut it shorter, not longer. You either have to export or use the wastes. Right now you are doing neither.> (and this is when I started having the issue with the rising PH: it goes up to 8.5)... <8.5 on it's own isn't a big deal.> Firstly, I've read up on algae at the WetWebMedia site. My local guru is clueless regarding the algae issue, as am I. Food isn't the issue. Lighting has been reduced (for about 2 weeks now) and I see an increase in the hair algae and a decrease in the slime. <Until you turn them back on again, and it will return, because the nutrient is there, but no needed light to grow. Get rid of the nutrient!> However, the PH is freaking me out. I'm not sure if it's an issue or not... It's been a while since I've had to remember all this stuff, and it's coming back slowly. <8.5 just before lights out isn't a problem.> I am using the Pinpoint monitor for the PH. It's only about 3 months old, so I don't think I need to replace the probe yet. <Wouldn't hurt to verify with a decent chem pH test anyway.> The tank is a 95 gal with a 30 gal (full capacity) sump (actual is probably 10 gallons). My protein skimmer is not very active, either. <Yep, I understand, make it go!> Of other mention is that I am using the Coralife salt versus Instant Ocean (it was far cheaper - is that a hint?). <BUT, is it REALLY???  This is a big problem, get rid of this salt and buy IO, on sale if you have to! Coralife uses the most screwed up buffer system known to man. It could just as easily result in calcium at 550-550 as well. Make sure you mix, heat and aerate your new water 12-24 hours before use.> Any and all input appreciated. Thank you. Bruce Webster <Go for it Bruce!  Craig>

Polyps and low PH - 2/23/03 I decided I wanted to try Corals out, I set my tank up with proper Lighting, water specs were good zero's, 1.025 SPG, 480 Calcium (a little high but not horrible) my watts per gallon are 4, and ph is 8.2. I bought a small Brown poly frag with 5 small polyps for $5 just to see how my tank would handle the coral, It took a week for them to open up, and only 2 did, the other 3 are dying I think, because they have shrunk considerably, should I pull this out? or since the 2 "live" ones seem to be doing fine now is it salvageable? <I say definitely! I would leave them in the tank. Part of the problem could have been the many adjustments they were put through from shipping to destination point, then wholesaler to retailer, and lastly, from their tank to your tank. Leave them where they are and let it go for about month, They will survive...... > Or could this hurt the tank? <I don't think they will hurt the tank. Keep an eye on the other inhabitants, and maybe add some carbon if you are not already. Increase water changes as well> also what is the best way to raise Ph? <Many to choose from. Check here: http://www.wetwebmedia.com/marphfaq2.htm> I am having a hard time keeping it at 8.2 it will sometimes drop to 7.8 for no apparent reason. <Possible the difference between your light cycle (not the Tron type) but maybe when your lights are off vs. when your lights are on? That type of difference is somewhat normal. See what you can find from the faq link above. In any event, leave the coral in the tank and give it time to adjust and recover. Good luck. Paul>

Low Low pH  - 2/22/03 Thanks to Phil on the Forum,<No problem, saw you needed a hand.> I just learned what should have been obvious: the pH being way too low!  I somehow overlooked the fact that the pH could drift without any critters in the tank (presumably just from the biol. filters running?)<Well, have you been keeping up with water changes and temp. control?  They play a factor!>  If you guys agree with that theory, does that mean I don't have to totally break down the tank, but just get the h2o parameters in line?<Nah, just get the H2O levels in line!>  I'd also like your opinion on the "cycled vs. sterile" debate for QT tanks.   I went for cycled cuz I don't think I could possibly keep up with the h2o changes I assume would be needed for the sterile approach.<Keep the tank cycled by doing a 5% water change a week and maybe once and a while dropping a very small amount of food in the tank.  IMO this is the best way to keep the tank up and running.>  I feel horrible about killing those 3 little guys!!<When you lose a fish it's really tough!  But learn from this mistake and move on.  This way you become a better aquarist!!  Hope this helps!  Feel free to ask anymore questions!!  Phil>

pH issues Hi to you all, Well, after a very easy year and a half of tests on the 75 gal tank we now seem to have a few little problems. <good to hear!> Tested the waters Sat, haven't tested them in over a month. <hmmm... here it comes :) > Saturday PH 7.8 (yikes!) CA 340 KH 4 nitrates are up too! <other than the very low pH... and the low ALK... and the high nitrates... it all sounds fine <G>> Buffered per instructions on bottle.  Actually I am conservative.  And used a little less than they said to. <always wise to do... its much easier to add a little more than take it out> Did a 10 gallon water change Retook tests this AM and the results are the same. <no biggie... good and bad things should happen slow in aquariums> A little nervous about being accurate with these tests but before they were all normal and so I think that the tests are OK.   <do check expiration to be sure... even check against another (LFS) test kit> I think that they definitely show that we are not in great shape.... So here goes. I need a little help with the sequence of what to do. Should I buffer? Should I slurry? Should I do both? <neither/none yet. Lets improve all and get the nitrates diluted with a series of good sized water changes (25-50%). Else you are wasting Ca/ALK by dilution after the buffered correction> I already did a slurry of 1/16 tsp of the Kalkwasser per Anthony's book and took a reading of the PH and it looked exactly the same. <no worries... nicely conservative and too low in this case> Do you take the reading right after you add the Kalkwasser? <about an hour or so afterwards> Don't know what I expected but now I am nervous about what to do..... <never forget in any circumstance: "Dilution is the Solution to Pollution"> I am reading like mad but just getting a little confused.  Any help would be appreciated. I prepared you for this Anthony......ah the learning process.  All would be fine if I didn't have a job too! Thank you...... <heehee... real jobs do get in the way :) I hope I never have to get one. In the meantime. 3 nice water changes in the next 2 weeks will get you in the ballpark... you can dose a small amount of Kalk nightly to support it. And a small amount of buffer 2-3 times weekly by day. No worries. Anthony>

Chronic Low Ph Problem Hello Bob. <Hi Shawn, Gage here this morning.> I was wondering if you could help me solve my low Ph problem on my 125 gal reef .It has been established for close to 3 years now.(1yr. as a fish and 2yr. as a reef only tank) .I have lots of SPS and some LPS as well as a few softies. My lighting setup includes (3) 175w 10k MH, (2) 55w actinic CF, (2) 55w 10k Supersun CF, (1) 110w VHO 50/50, and (1) 110w VHO 03 actinic fluorescent. The total lighting is about 11 hours with the chiller keeping the temp between 78 and 82 degrees. I have a Knop calcium reactor and a G3 skimmer. Plenty of live rock (maybe 200 lbs) with a straight live sand bed. My water parameters are as follows : Ph goes between 7.8 - 8.1 ,Ca.300-320, Mg.800-1000, KH averages 10.0 - 12.0 .The Spec.Grav. is an average 1.023.Livestock includes 8 fish mostly small gobies, blennies & Basslets with a 4 inch Maroon clown who loves his 12inch pink anemone. The corals are many Acropora and Montipora frags , 4 parent Acropora colonies, plus many others hard and soft corals . Most of which have been fragged in some way or another. I have 7 Total powerheads (not including the 2 on the protein skimmer) with 4 on a wave maker device pushing allot of water inside the tank so I've got excellent water flow in most areas. I'm using the AquaCraft 2-part Marine Environment Salt mixed with my own RO water. After a 35 gal water change, the Ph. will stay about 8.2 for a day or so than drop again. Of course I've tried the buffer additives and none seem to have a lasting effect as I'm also very weary of dumping lots 'junk' into my tank. I dose Magnesium and iodine every now and again. twice a month) I've also tried the aeration test and the water sample does indeed jump .2 Ph points after 1 hour of aeration. I have a fan pointed at the sump and both fans that cool the halides ripple the water surface quite well. I'm kinda stuck, Do I need to go and buy some super duty air pump and put large airstones in my sump? Also what's the biggest water change ratio you can/should do? Is 80 gallons too much? Maybe my 25% isn't enough. I've tried everything (including (5) 50 gal water changes in a one week period) <wow, that is awesome if you can keep it up, but probably will not fix the PH problem.  I like to go with 1/3 weekly, but small frequent changes are best.  Large water changes in your situation could cause problems due to large pH swings.> thinking that the water was chemically imbalanced. After each water change the Ph goes to 8.2 - 8.5 until that night when it falls to 7.7 - 7.9 and stays low all month. Much Thanks to you and your crew and keep up the great job on the website. It's a very useful tool for the hobby Shawn <If aerating a sample of water raises the ph it sounds like you have a problem with accumulated CO2.  It is a common problem in insulated houses.  Sometimes just a lack of aeration in the tank.  If you have access to a garage (no fumes or cars) or with water resistant pumps (pond air pumps) you can pump air from these "outside" locations in to the sump or skimmer and that takes care of the whole problem without adding fans or huge aerating skimmers.  There is more information on these problems in the FAQs below.  Best Regards, Gage http://wetwebmedia.com/marphfaq2.htm >

- Using Baking Soda - Dear Crew: <Hello, JasonC here...> When I use the baking soda for pH rise, I premix the baking soda with tap water and put into the tank, I notice a DROP in pH!!! What happen?? <You are supposed to premix the baking soda in a small container of tank water - not freshwater.> I am currently using buffer powder dKH, Tetra CB additives Part A and B and Liquid Calcium, the above products are made from Kent marine. Why is that?? <I'm not sure I follow your question here...> Eric <Cheers, J -- > pH problem I set up a 29 gal, fish only marine tank about 6 mo.s ago.  I have a Jaubert's style plenum with about 2.5" substrate, hang on bio-wheel power filter, and a cheap in the tank skimmer.  I perform biweekly 30% water changes with Reef Crystals salt and RO water.  The lighting also leaves a lot to be desired (1) daylight and (1) actinic.  Funding is a problem but I do the best I can. The tank houses (1) Percula Clown, (1) Scooter Blenny, (4) Hermit crabs and(1) Pencil Sea Urchin.  Last night I tested the water and noticed the PH had dropped to about 7.8-8.0.  I added a solution of 1 tsp SeaChem's Marine Buffer which I mixed with about 1 cup of RO water.  Today my hermits are gone and the PH is a solid 7.8.  What happened?  I read your articles and PH/Alkalinity and I think I have a grasp of the concept that alkalinity stabilizes PH but I am not sure of the measurements.  I measure approx. 11-12 dKH but I can't seem to get the PH up. Is KH the same as alkalinity? I must tell you I have been using my KH test from my freshwater test kit to test my salt tank. Is this the problem?  If the KH is high, shouldn't the PH come up? From reading you articles, I realize these questions are low on the experience scale but you gotta start somewhere. Thanks, Mark <Nah, not really! KH and dKH are both alkalinity. 11-12 dKH is a good alkalinity level, but I would use a marine test kit, like Seachem or Salifert. I would also test calcium, and in your case, magnesium. Perhaps take a sample to your LFS and have these tested there. Low magnesium will contribute to depressed pH as will acidic wastes (ammonia/nitrite/nitrate) which could come from your plenum/bio-wheel set-up. Are you buffering your top off water? This could also contribute, but would show up in lowered alkalinity as well.  Make sure you aerate your new water for 12-24 hours and test and adjust alk/pH/calcium if needed. This may be your problem, test your new water.  Hope this helps, not to worry too much with slightly depressed pH, but do find out why.  Craig>

Low Ph in 125 gal reef Hello Bob.<Your stuck with Don today>I was wondering if you could help me solve my low Ph problem on my 125 gal reef (150 total gallons). It has been established for close to 3 years now.(1yr. as a fish and 2yr. as a reef only tank) .I have lots of SPS and some LPS as well as a few softies. My lighting setup includes (3) 175w 10k MH, (2) 55w actinic CF, (2) 55w 10k Super sun CF, (1) 110w VHO 50/50, and (1) 110w VHO 03 actinic fluorescent. The total lighting is about 11 hours with the chiller keeping the temp between 78 and 82 degrees. I have a Knop calcium reactor and a G3 skimmer. Plenty of live rock maybe 200 lbs) with a straight live sand bed. My water parameters are as follows : Ph goes between 7.8 - 8.1 ,Ca.390-420, Mg.800-1000, KH averages 10.0 - 12.0 .The Spec.Grav. is an average 1.023.Livestock includes 8 fish mostly small gobies, blennies & Basslets with a 4 inch Maroon clown who loves his 12inch pink anemone .The corals are many Acropora and Montipora frags , 4 parent Acropora colonies, plus many others hard and soft corals . Most of which have been fragged in some way or another.   I have 7 Total powerheads (not including the 2 on the protein skimmer) with 4 on a wavemaker device pushing allot of water inside the tank so I've got excellent water flow in most areas. I'm using the Aqua Craft 2-part Marine Environment Salt mixed with my own RO water. After a 35 gal water change, the Ph. will stay about 8.2 for a day or so than drop again. Of course I've tried the buffer additives and none seem to have a lasting effect as I'm also very weary of dumping lots 'junk' into my tank. I dose Magnesium and iodine every now and again. twice a month) I've also tried the aeration test and the water sample does indeed jump 2 Ph points after 1 hour of aeration. I have a fan pointed at the sump and both fans that cool the halides ripple the water surface quite well. I'm kinda stuck, Do I need to go and buy some super duty air pump and put large airstones in my sump? Also what's the biggest water change ratio you can/should do? Is 80 gallons too much? Maybe my 25% isn't enough.<Actually, you may benefit from more frequent, smaller changes(5%) a couple times a week. Make sure the change water is at the parameters you want the tank to be at and over time things should stabilize.> Anyhow , Much Thanks to you and your crew and keep up the great job on the website. It's a very useful tool for the hobby <Thank you> Shawn

- pH Meter Questions - Hey gang hope all are well? <I am thanks for asking.> wanting to buy a Milwaukee ph 44 meter for dosing Kalk. On the calibration solution what should I buy ph 4.01,7.01 or 10.01 should it be in liquid form or powder. <Well, you have to have at least the 7.01 and because the majority of the readings you will be taking will be above 7.0, you should also obtain the 10.01  - both in liquid form, it's easier that way.> do I need electrode rinse solution or storage solution. <Follow the manufacturer's directions.> wanting to go to Anthony's slurry method . tired of the Kalk missing cant wait for the new book  already bought and paid for- Christmas gift thanks to my beautiful and understanding wife  this hobby is addicting  thanks for all you do.   Rocky <Cheers, J -- >

Re: High pH my tank is about ready now for fish but the sea water ph level is 8:7.is this to high and if so how do I lower it .what fish do you suggest I put in first, I was thinking of starting with a clown fish. <I would start by getting a second opinion by a different PH test, that is scary high.  If it is correct you will want to run a full test (calcium/alk) of the water and look at any additives that are going into the tank  to see if we can pin point what is causing the PH to be so high. -Gage>

- High pH - Hi! <Hi, JasonC here...> I have a 55 gallon salt tank...It's been up and running for 7 month's or more....Everything has been good with it. I have 6 damsels, 1 mandarin, 1 scissortail goby (which I never see eat)...The past week I tested the water & my PH jumped to 8.8...It has always been at 8.2 ...Ammonia 0 Nitrite 0 & Nitrate 0..I can't figure out why it jumped up after all this time. I do also have 4 red legged hermits, 1 peppermint shrimp 1 emerald crab & a chocolate chip starfish in there.. <Have you been adding anything to the tank to supplement trace elements?> What can I do to lower the ph? <You can try the ph-down products, but you need to use the product sparingly, and there are some other possibilities. pH tends to fluctuate during the day, with the lowest readings at the beginning of the day before the lights come one, and the highest readings at the end of the day before the lights go out. You might want to try several tests over the course of a day and get an average from that. Also, depending on what you are using for the pH test, your reagent(s) might be near the end of their useful life and require replacement. You can double check by taking a water sample to your local fish store for confirmation.> Please help before I lose any of fish or inverts, Kim <Cheers, J -- >

Late night emergency I hope that I am not to late to get an answer.   <we work almost round the clock here... 4AM and all's well> I did a water change in our tank today.  The ph on our 75 gal saltwater tank was 7.7 which is a little low.   <actually... for a daytime reading that is extremely low and indicative of a serious problem IMO. Assuming that your test kit is accurate, the night-time pH will be .2-.4 lower typically which means you could perhaps fall to 7.3 at night! That is way scary. A safe pH range for marines is 8.2-8.4. With reef invertebrates it is actually higher still. You do not want to drop below 8.2 at night> But with the water change it boosted up to 8.0.  The salt level is with in normal.  I kept the temp at 78.  But tonight before I turned the tank light off I noticed that every fish in my tank was breathing hard.   <please put fresh carbon in ASAP fearing a contaminant> I have seen fish breath like that when they are put in water with chlorine. <many possible reasons for it> To double check my water, I used our pool chemical test for chlorine to see if there was any chlorine traces. it came back with not a trace.  What could be causing the heavy breathing of the fish?   <water chemistry... a pending disease outbreak (have you added any new fish lately without a proper quarantine period, etc). Many possibilities here without us knowing more information, symptoms and history> You have always given us great advice on our tank.  I just hope they won't all be floating upside down in the morning.   <that makes two of us!> Thanks.  Vickie Sorensen <be prepared to do another water change in case a contaminant is the problem. Look for other symptoms too. Best regards, Anthony>

Re: pH control Hello, I love your guys' web site.  It's been very useful! <<Thank you very much, we try.>>   But I'm having a problem with pH.  I have a large freshwater aquarium with koi and goldfish.  The ammonia is nil, the nitrates/nitrites are also nil, and the pH is always around 6.0-6.2, even though the tap water is 6.6 or so.  I know that koi prefer a pH of around 7.4, so I was wondering how I could raise the pH without using chemicals.  Will the lower pH really affect the koi?  Is it important to raise the pH? <<Well, your Koi are adapted to this lower Ph but they would probably be more comfortable with it being a bit higher. There are commercial Ph adjusters but you can raise the Ph easily and much cheaper yourself with baking soda. Dissolve some baking soda in some tank water and then slowly pour around into the tank. Be sure to only raise the Ph a small amount at a time so you don't send your fish into Ph shock which can be fatal. It will take a while (possibly several weeks) to get the Ph up to the 7.4 range that you want so be patient. For more info on using baking soda use the Google search box at www.wetwebmedia.com to do a search for baking soda.>> Thanks a lot for your help, Phil <<You're very welcome. Ronni>>

Re: pH stability how do get my ph to stay at 8.6  Thanks in advance <there are several products on the market for increasing pH above 8.3 (baking soda and like buffers will not). The most common and effective way to do so is by use of Kalkwasser (calcium hydroxide). It has so many other benefits too (read about them for days in our archives here at wetwebmedia.com). Be sure to dose slowly and judiciously. Read in the archives too about my convenient "Kalk Slurry method" for doing this. Test for calcium at the same time and be sure to keep it under 425 ppm. Best regards, Anthony>

Re: Temp and PH Hi Guys, I know that temp affects the Specific Gravity of a tank, but does temp affect PH as well.   How do SG and PH correlate? <Not related as far as I'm aware>   Thanks in advance for your help.   The web site is invaluable for new starters like myself. <Glad to find it of service. Bob Fenner> Regards Glen

High PH I have a question regarding high PH. I have a 180gal reef tank (230 total gallons of water with refugium and sump). My Ph is between 8.5 and 8.7 depending on time of day/night. Will having a PH this high cause me any problems and if so is there a good way of reducing it. My source water is above 9 and even after it passes through my deionizer it is still in the high 8's. All other water parameters are within accepted range and all fish and corals seem to be doing fine. Any advice would be greatly appreciated. Thanks <A very high pH could be a source of problems. In my opinion, 8.5pH is not too high...If you are experiencing problems, you could consider mixing some RO/DI water with your source water to help lower the pH...You'd have to do some experimentation to find the right "mix". Keep an eye on things here. If it becomes necessary to take the action, do so carefully. If you are not having any problems, I'd just keep observing...Good luck! Scott F.>

- Odd pH Fluctuation - Hi Jason. <Good morning.> I don't know if you remember me, but I wrote you last week about my pH being a reverse of what is should be. <I do remember.> Low in the day, high at night. <Right.> I figured out my problem! <Oh good.> I have 2 250W MH and 4 65W PC (2 Actinics 2 10K daylight).  Every time I turn on the 2 PC daylight bulbs, my pH monitor drops from 8.4 to 7.99 instantly.  Every time.  Then when I turn it off it raises to 8.4 just as quick.  Amazing. <Perhaps not so amazing, but glad you found it... on the same day I replied to you last, I was walking the dogs with Bob and said, "You recall that guy who is having pH problems... I wonder if it is a problem similar to when you run the vacuum cleaner and it dims the lights... in other words, the power supply is sensitive to fluctuation. Sounds like that's what it is.> only happens with the PC daylight bulbs.  Everything is on the same circuit too. Weird. <Again, not really weird when you think about it for a while... but did have us both looking in the wrong direction.> Just thought you would like to know. <Much appreciated.> Brad <Cheers, J -- >

- Investing in a Digital pH Meter - Hi WetWebMedia, <Hi, JasonC here...> I recently started a small marine aquarium business.  Because I have a number of different systems, I often go through a test kit rather quickly.  I've been thinking about the digital testers which are supposedly highly accurate, the only disadvantage is that their an investment. <Well, any piece of equipment that helps you do your job more effectively would be an investment, but the $60-70 you would spend on a handheld meter would be a rather small one, but quite invaluable in the long run.> I really need something quick, accurate, and reliable.  If you could recommend a couple to me I would greatly appreciate it. <I use the Milwaukee Instruments Smart Meter.> Thanks and keep up the good work! -Alicia 5th Day Aquatics <Cheers, J -- > - Re: Digital pH Meters - Do you recommend any specific digital pH testers? <I thought that I had put that information in my previous response. I've used the Milwaukee Instruments Smart pH Meter with good success... do believe it is a pH44. Cheers, J -- >

High ph problem Hello Anthony, here is a slight problem:  my ph in my reef tank is around 9.3 during the photo period and only drops to about 8.6 at night.   <if true, that would be more than a slight problem... but I highly doubt your tank is over 9 pH without a catastrophe. your problem likely is slight: inaccurate test kit. Please do verify the accuracy of this test on another kit and brand separately first> I do not have my calcium reactor hooked up yet and I hope to clean the probe with a toothbrush and recalibrate it today, although I don't think that is the problem.  I've held off on adding the Kalkwasser slurry for a couple days now and I am not adding any buffer either, at least till this high ph goes down.   <equally dangerous... we need to figure out first if the pH is really that high (unlikely) and then if so, who did it get there without a reactor> I don't know what I can do to get it down, <simply do water changes... dilution is the solution to pollution. A series of 25-50% water changes> I don't want to do anything drastic too fast. <stopping buffer and Ca additions is far more drastic bud if the pH is bogus (or having added so much previously without metering and testing if it is not bogus)> Water change?  How much?  I just did one about 4 days ago, 10 gallons on a 90 gallon reef that mostly has LPS and soft corals.   <way too modest of a water change... larger please here> Is this common for this to hold at this ph for any certain length of time?   <impossible in practical applications with fish and corals that are fed almost daily> There is also some macroalgae and some of my live rock that might also be attributing to the extra use of carbon dioxide (acid) thus driving the ph up in the tank, <nope... you'd have to have a garbage can full of algae to get that high. It would also indicate a serious aeration problem. Did the skimmer die recently (halting aeration in a stocked tank)?> but this was not a problem before, this is recent, not more than 2 days.  Would appreciate any input of yours, thanks Jamie <best regards, Anthony> High ph Anthony I just mailed my sister who lives with me and asked her to read the ph and it is currently at 8.9 , I'm at work right now , the metal halides are on for a little over 2 hours by now.  You mentioned having the skimmer off...I did have it off for a couple days to wait till I could fill my sump up with more R/O water I don't practice doing that though).  It is back up and running as of yesterday.  Why would that give off a high ph if it were off  ?   <in the presence of high photosynthetic activity with poor aeration (like in "green" unicellular ponds) one will notice wild swings on such extremes. The aeration tempers the process> I would think it would do the opposite and oxygenate the water less, thus having more carbon dioxide and less oxygen.   <true... but hen I would have expected the difference between night and day readings to be closer (both scary high). The fact that your night pH was .9 lower was staggering and indicative> Just to let you know that I didn't unplug the skimmer to fight the high ph problem , but my high ph problem did start about then now that I think about it.  thanks bro <do let us know how it works out, my friend. Best regards, Anthony>

- pH Problems - Hello WWM crew! <Hello, JasonC here...> After reading thru the FAQ re: pH and Alk, I have learned a number of things but also let me with a couple of questions. My set up is 90 gal SPS and clam reef. 70 gal Refugium with a plenum, and 70 gal sump.  I have about 15 x circulation in the display with SPS corals. My Refugium houses about 50 lbs. live rock on a reverse daylight period, with some hair algae problems. Here is my concern. During the day hours my pH is 7.99-8.02.(9am-9pm) At Night my pH is 8.3-8.45.(11pm-7am) From everything I have read it should be the other way around? <It should... although with a refugium on reverse daylight, the pH should swing even less.> I have about 150 lbs of live rock, 250 lbs of live sand. AquaC 400 skimmer dose B-Ionic, Iodine, Stront, and activated carbon.  I use RO/DI for top off and water changes.  I do have a problem of: calcium carbonate? <Are you doing anything for alkalinity?> Could the problem below cause my inverse pH change? <Could be... a sign of too much calcium or too high an alkalinity... you can likewise test your water for excess CO2 by simply placing some tank water in a measuring cup and putting an air stone and pump to work on aerating the sample. Take a reading when you start and also later in the day or following morning. If the pH goes up, you probably have excess CO2 from somewhere; could even be from inside the home. You don't perchance live up north and have all the windows sealed tight, do you? Might just need a dose of fresh air.> Thanks to Anthony for the problem solving below. >I have is over the last couple of months I have noticed something leaching out of the water and covering the pumps impellers and heaters of the sump, but don't notice it on anything else. It is a white cement like substance that can only be scraped off glass by a razor blade. >Also the substrate in my plenum is starting to "crust over" or "cement" together. I feel a pH swing of .4 or .5 per day is cause for concern. <I would agree.> Keep up the fine work.  I read the FAQ nearly daily Brad Stefanko <Cheers, J -- > - More on pH Problems - Thanks for the quick reply Jason. <My pleasure.> I do live in Michigan, and in winter it can get cold. <And likewise, these houses usually seal up tight.> I will leave the windows open for a few hours to the room where sump and refugium are.  Hopefully that will stabilize my pH swing. However, if I had a problem with too much CO2 in the water, wouldn't the pH just stay constantly depressed, rather than a swing high (8.45) to low (7.95)? <Unless, for some reason there is more CO2 in the house during the evening, say when the heater is running more often.> Could lighting have an effect on a Pinpoint pH monitor? <I wouldn't expect an affect on the monitor device directly, but perhaps a change due to increased photosynthesis in the sump?> I noticed my pH monitor start to slowly rise as soon as the MH turn off. <There's a clue in there somewhere. Perhaps try a new probe on that pH monitor... they do age, pretty much done in about a year.> My water tests are: Cal=390, alk=3.36 Meq/L (if you take 168ppm alk and divide by 50 according to LaMotte) A world of thanks, Brad Stefanko <Cheers, J -- >

The Mystery of The Unchangeable pH! (The Saga Continues) Scott F., <Here with you tonight!> Continuing with our discussion of the low ph in my system and water change water, I tried a new angle today.  Same water (2 gallons tap + 3 gallons distilled) plus Seachem Marine Buffer + Instant Ocean. The only difference is that I did not aerate at all.  When I did aerate for 24 hours, the ph of the final mix was 8.04.  With absolutely no aeration, the ph was 8.01. <Grr...> The only plus out of all of this is that I have performed three water changes in the last seven days!! <What's the old expression- "when life gives you lemons, make lemonade? Seems applicable here. Hey- what is the pH of lemonade...?> I get almost zero fluctuation in my ph between day and night (excepting, of course, when I dose Kalk at night). Alk is steady between 9 and 10. Got something else in your bag of tricks? Sincerely, Mark Schwartz <Well, Mark- my bag runneth empty here! I guess the good news is that you have stable parameters, with little fluctuation. Also, the pH is not super high- and within "normal" ranges, but certainly not dangerously low, either. Take comfort in this! I'll keep researching this for you with my colleagues here on WWM, and let you know if I find anything else...In the mean time, just stay the course here...keep being consistent. Catch you later! Regards, Scott F>

Low pH? (Pt 2) Scott F., <Here again!> I tried your methodology.  I also took heed of your comment about how salt mixes are manufactured assuming some level of minerals, etc., in the water. To this end, I made a 5 gallon water change as follows: 1)  2 gallons of tap water (central Indiana liquid limestone: ph = 8.03 and dKH = 17) 2) Added to 3 gallons of distilled water (I normally use 5 gallons of distilled) 3)  Aerate for a full 24 hours (I normally aerate 16-18 hours) 4)  Add 1/2 teaspoon of Seachem Marine Buffer ph 8.3 and stir. 5)  Add 3 3/4 cups of Instant Ocean. (Well known to mix up at ph 8.3) 6)  Stir until any trace of cloudiness is gone.  About 8-9 minutes. I then tested the ph with my Pinpoint monitor.  Take a guess: How about 8.04 ?!?! What the heck????   It's GOT to be something environmental.  But what? <Wow! That is frustrating...I'm wondering if you should experiment with just the tap water, and no distilled...?> If I add 1/2 tsp. of Seachem Marine Buffer to 16 ounces of RO water and test, I get ph = 8.3.  Now this I expect. My reef system has a near identical ph to my tap water Water parameters as of 5 minutes ago (water change done 2 hours ago): Parameter        Test kit used Ammonia = 0        Aqua. Pharm. Nitrite = 0        Aqua. Pharm. Nitrate = 0        Aqua. Pharm. Temp = 79 Calcium = 350        Seachem Mg = 1280            Seachem ph = 8.02          Pinpoint monitor spg = 1.024        ESHA Marinomat dKH = 10           Aqua Pharm. Any thoughts?  <Hmm...My limited chemistry background is being seriously challenged here! One other thought for you...Is using RO water a practical and affordable alternative for you? Since the RO readily buffered to a pH of 8.3, I'm wondering if there is some factor in the tap water or distilled water that you are using which is "eating up" the buffer...Another experiment for you to try: How much buffer does it take to get your source water up to 8.3pH? This may yield some clues. Give it a shot. You may want to contact your local water utility as well to get some more clues ass to the composition of the water...>   I have two young children who don't aggravate me near as bad as this problem -- and that's saying something :-) Frustrated. Sincerely, Mark Schwartz <I hear you, Mark! See if these little experiments get us anywhere, and we'll try to pick it up from there...Craig Bingham, where are you???>

pH Meter Calibration Questions Hello, oh wise ones.  Have a question, have not used my American Marine pH monitor in awhile and can't find info from the manufacture. I searched the site and did not find. How do you calibrate?  I have new standard solutions #7 and #10.  Any help, as always is greatly appreciated.  Thanks Brian <Brian- contact the manufacturer directly at: loudell@bestweb.net>

High pH bad equipment David, Just to fill you in, my Neptune ph tester was way out of whack, my ph kits show the water around 8.4-8.6. So everything was fine, I need to work on my patience level though !. PS How often should I change water & do I sweep the debris & crushed coral every time if it is a weekly 5 gal. change. <Whew! What relief! I knew it was hard to believe that the pH was rising. It just doesn't happen without excessive abuse of additives or false readings due to faulty equipment. I would gently vacuum every time you do a water change. I would plan on changing between 10% and 20% weekly and 20% is on the high side> Thanks !!! <You're welcome! David Dowless>

pH Swings and Other Bad Things (That's What Nightmares Are Made Of> Hi guys. <Hi there. Scott F with you today!> this is my problem. My ph falls to 7.7 during night and stays at 8.0 during the day. My tank is 100 gallons combined. Reef. Have maintained reef tanks since 1997. cal 450 ppm (Salifert) alk 10dkh (Salifert) ph 7.6- 8.0 (pin point monitor-calibrated and double checked against a friends monitor.) I add Kalk with makeup water, this maintains my calcium at 450,but something is keeping my ph from going up. I have had a recent algae bloom in the tank. Algae was overtaking my tank. <Well, as you are probably aware, nuisance algae are largely the result of excessive nutrients in the water, and excess nutrients are a contributing factor in depressed pH levels. Aggressive protein skimming and regular water changes (as well as re-vamped husbandry techniques) make a big difference here> This is a brief description of what happened. I used to add Sea-chem reef calcium and reef complete, along with reef builder for alk control. I have dosed this way for well over a year. My dosage was 1 tsp every 2 days and my makeup water with reef builder. I monitored the tank every week and when all was stabilized every 2 weeks. My test kits are Salifert. In October I take a calcium test and notice my calcium is off the chart, over 500 ppm. I re-take the test it is still over 500pmm. <How was the alk reading at this time?> I do a 20 gal water change. (RO water) Still over 500 ppm. I take a water sample to a friend and he confirms the same. I then proceed to change 50% of water. 12 hrs later still over 500ppm. (mind you my alk is always around 11 dKH) <ok- answered that question!> I wait 1 week then do another 50% water change.12 hrs later, my calcium is at 490,it is slowly coming back down. I must add that all during this time I stopped adding cal supplementations. <Well- one observation here: You are making HUGE water changes, which will definitely have some strange effects on the chemical dynamics occurring in this tank. Too much of a good thing, IMO. How about reducing to less tedious, more effective, 5 percent water changes twice a week? Small changes, done regularly, are much more effective and less stressful on you and your tank than the massive ones that you are doing now. Not to mention the savings on salt mix, time in water preparation, etc. Give 'em a try, ok?> Have stopped using sea-chem. 3 days later I do a 25% water change and finally get 450 ppm. Back to normal in 2 weeks. My ph at this time was around 8.2.3-4 days later and this overnight - my tank was smelling of algae and algae was everywhere in sight. Overnight. I proceeded in doing water changes to no-avail. <Wild theory with portions that may have some possible merit, which you should investigate: The massive water changes are somehow causing damage to your biological filtration, some nutrient accumulation is occurring as a result of this interruption, and the algae is benefiting from all of this...Just a theory for you to check out-maybe it will give you some other ideas for things to check out...> My ph is at its lowest at night 7.6. <The day/night fluctuation of pH is normal...> I bought a uv sterilizer, and now after 3 weeks of 24/7 usage the algae is slowly going away. I then decide to use Kalk for cal instead of sea-chem. But my ph is the problem. Is it the algae that is keeping the ph from rising? <Well, plants and animals produce CO2 in the dark hours, which can drive down the pH> I have lost all my fish during this algae bloom. <Sorry to hear that> What caused the bloom of algae? My fish were helpless and kept swimming near the surface. <Sounds a lot like oxygen deprivation/excessive C02. Did you also check nitrite and ammonia during this event?> I added powerheads and an air pump to get fresh air into the water, to no avail they  all died. I have a powerhead blowing in fresh air into the tank. I have fans blowing air across the water. This ph thing has got me baffled. Why will it not go up higher than 8.0. I must also add that although all my fish died, none of my SPS corals died. Also my water is made from RO/di system. Any clues? Thanks, Dan <Wow, Dan...a number of possibilities here. The fishes seem to have been poisoned by excessive C02 or lack of oxygen. Possible contributing factors were lack of circulation/oxygenation, biological instability caused by large water changes, and, perhaps, the water preparation techniques that you were using with your R/O water. Remember, R/O  can be rather "unstable", for want of a better term, and vigorous aeration and buffering prior the mixing of salt will make a big difference in the water's stability. And, as you know- stability is very important in a marine aquarium system. I'd do a complete review of your system, it's components, bioload, husbandry procedures, and basic water chemistry. There is a massive amount of information about these topics on the wetwebmedia.com site! Sometimes, the simplest changes yield the most dramatic results. Also, keeping things simple (executing small water changes frequently, for example) makes for a better, more stable long-term system. Do that review, re-work your system, procedure, and philosophy as needed, and I'm sure that you'll see a turn for the better in the near future. Good luck! Regards, Scott F>

This Water Is On Acid? Guys, <Scott F. your guy tonight> I purchased a brand new Pinpoint ph Monitor last week because I was sick of differentiating shades of purple while trying to interpret my system's ph. <I can relate to that plight! It took me a long time to remember not to mix my whites and reds in the laundry...well-that's another story...> After calibrating (it came with ph 7.000 and 4.000 solution packets), I placed the probe in my sump.  Horror!!  My ph is 8.02 in the early morning. <Don't be too freaked...Remember, in the dark, an excess of CO2 is produced by the respiration of the animals and plants in your tank, and the C02 lowers the pH as a result. During the early morning hours, your tank's pH will generally be at or near it's lowest level. Try that reading around 3:00Pm in the afternoon (after the tank lights have been on for several hours) and under most circumstances, your pH will be quite a bit higher. And 8.02 is not a bad number for your "low" pH reading, IMO!> I use Kalk for all top off water and it is still this low?! <Well, Kalkwasser, when dosed improperly, will not help pH levels in most instances...DO read up on the wetwebmedia.com site regarding the proper dosing of Kalkwasser. Also, Anthony Calfo gives some excellent info, on this topic in his "Book of Coral Propagation".> I purchased four (two 7.000 and two 10.000) packets of calibration fluid yesterday.  I recalibrated using one 7.000 and one 10.000 packet. It was off by 0.01 on the 7.000 and 0.03 on the 10.000. <That's not good!> The unit is only nine days old and has now been calibrated twice. I was extra diligent this time. It is working properly. <Cool!> Anyway, now for the bad part.  I purchased a brand new 200 gallon bucket of Instant Ocean yesterday as well (the only salt I have ever used). I mixed up my weekly 5 gallon water change:  5 gallons of distilled water + 1 tsp. Seachem Marine Buffer ph 8.3 + 3 1/2 cups of Instant Ocean salt.  Mix thoroughly and aerate overnight (about 18 hours) for use this morning.  I measured the ph of the new aerated water.  8.02 ?!?!?!?! WHAT?!?!  How is this possible?  The Seachem Marine Buffer is ph 8.3, and Instant Ocean is supposed to mix up at 8.3.How in God's name am I getting 8.02? Any thoughts?  This explains, to a large degree, why my system ph is so low, but I don't understand how this is possible. Sincerely, Mark Schwartz <Well, Mark, remember, distilled water (or R/O) for that matter, has almost no general hardness (i.e.; buffering capacity) and can produce pH results in the acidic range. I'd aerate the water first (overnight) to drive off the carbonic acid present in the water, THEN dose the buffer (according to instructions), THEN mix the salt in. Salt mixes are usually formulated with the assumption that you're using water with "normal" mineral levels and pH, so aerating, then buffering first before mixing the salt should help. You can read up on the topic of water preparation on the wetwebmedia.com site for a lot more detail than I can present here. Keep up the good observations and refine your techniques as you learn. I know that you'll see the readings that you're shooting for. You are doing great! Regards, Scott F>