Caulerpa... keep it under control  6/23/07 Hello Crew, I have a small (55g) marine (FOWLR) tank with a fairly heavy bio load and ever since we set it up we've had a very heavy forest of Caulerpa growing in one end of the tank. The growth was so lush we often had to cultivate it to keep it from taking over the tank. <Good practice... keep it regularly pruned> 5 weeks ago I added a BioBak skimmer and a separate Maxi-flow power head, just to increase circulation. Coincident to this the Caulerpa started to die off by breaking into small, 1 inch pieces that drifted around the tank until we scooped them out. <Good, scoop it out, pinch it off till there are no whitish, breaking pieces.> The power head corrected a dead spot in circulation where the Caulerpa centered, so my question is which is more likely: The current disturbed the plant -- or the skimmer took the plant's nutrients from the water? Or .. a third option? Thank You, Allen <These and the fact that the Caulerpa may be poisoning itself with a sort of bio-feedback metabolite reaction. Bob Fenner>

Re: Caulerpa   6/24/07 Thank you for the response, but this may be one of those cases where we are looking at the same thing from different angles. I liked the Caulerpa and want it back. <Ahh, I see... and apologize for my usual brevity... it is my desire to be understood... I do understand this now... and my response is still the same... Akin to your suggestion that an influence here could be (and is likely) nutrient limitation, the cutting back of this population will go a long way to ensure its survival in this setting> I didn't intend for two things I did for the benefit of one part of the bio-cycle to turn around and damage another part of that cycle. If I caused this, then the correction is to reach a balance of sorts: I can reposition the power head, leaving a smaller dead sport or I can cut back on the skimming in order to leave more dissolved organics for the Caulerpa. BUT ... I don't know if either of those is most likely to be the problem and I'm not sure how I could combat the plant poisoning itself. Maybe what I should be asking is if there is an FAQ on cultivating Caulerpa rather than removing it? Thanks again, Allen <Well-stated... I would encourage you to move part of the Caulerpa to another/isolated system for possible recolonization should you lose the current/resident one... and STILL to reduce the overall biomass, by about a half here. Cheers, Bob Fenner>

Caulerpa Going Sexual - 04/05/06 Hello - <<Howdy>> Thanks for the great postings in the past... <<You're welcome>> I have a strange situation going on in my tank... <<Ok>> I have a 75g FOWLR tank - Marineland Biowheel wet dry - Seaclone 150 protein skimmer.  I've been growing 2 types of macroalgae in the tank.  About every 2-3 weeks, a section of the Caulerpa seems to die off - it happens early in the morning, shortly after the light comes on - the tank goes cloudy and a section of algae turns white. <<Mmm, yes...A sexual event.>> I do a partial water change, remove the dead algae and everything goes back to normal for a few more weeks. <<Indeed...do keep this up as these events take place as there is possibility for severe fouling of the water.>> I'm doing 10% water changes weekly using RO water and Instant Ocean salt - all water levels are normal (pH=8.3, sg =1.023, ammonia = 0, nitrites = 0, nitrates = less than 10ppm, calcium is normal). What do you think is going on?? <<You are witnessing the algae do what is commonly referred to as "going sexual" and releasing gametes, other products in to the water (can be problematic in large quantities).  This is triggered by the day/night cycle and is why you see it happening after the lights come on.  Do have a look through our FAQs re...here's a good place to start (http://www.wetwebmedia.com/caulerpaalg.htm), and be sure to follow the associated links at the top of the page.>> Thanks for your help!!! <<Quite welcome.  Regards, EricR>>

Caulerpa going sexual - 22/03/06 Hi, here again requesting help. <Hello Edwin. John here with you this morning.> Have kept a 10gal refugium under my 55gal aquarium for almost 2 years. Have used feather and grape Caulerpa in addition to 4 mangrove plants in it since the beginning. During this period of time I have experienced some problems with the feather Caulerpa in terms of it growing very well for some time then it starts to turn white and disintegrates. With time I learned to read the signs when this was going to happen and I just take out the dying ones to avoid the disintegration in the water. Then I switched to grape Caulerpa and didn't experienced the die-off for several months. The strange thing is that for some time the grape Caulerpa have been disappearing gradually without signs of whiting like the feather and I am not sure if it has to do with the same phenomena or the reason might be an emerald crab that I added 2 or 3 month ago. I do not think is something related to the water parameters since I have not change anything in the water change schedule or the light schedule, everything have remained constant, even the mangroves have grow like crazy(2 of the plants already reached the bottom of the main display and started bending as they grew). Any suggestion will be appreciated. <What you've observed is correct: Caulerpa will undergo reproductive episodes that leave it white and dead, and foul the tank. Please look through our FAQs - and indeed the 'net at large - for many accounts of Caulerpa "going sexual". Constant pruning, or 24/7 lighting, are the only proven methods to mitigate the risk. <<Though not eliminate it. RMF>> For these reasons (and actually many more), other macroalgae are generally preferred over Caulerpa by most aquarists. Best regards, John.> Algal Bloom, Excess Nutrients, or Sexy Caulerpa? >Hi crew, >>Greetings Robert. >My tank has been cloudy (white on top, yellowish green on bottom) for about 2 weeks now.  I've been perusing articles and concluded that it's either an algae bloom or some Caulerpa gone sexual. >>Well, my own initial reaction (assuming you have Caulerpa in situ) is that it could be.  If it's gone sexual the "plants" themselves tend to die, dumping lots of nutrients in the water, which can in turn cause a micro algae bloom. >Don't have a phosphate test because my LFS is out.  Other parameters are normal (pH 8.2, SG 1.022, ammonia, nitrite, nitrate all 0).  Tank is 120 gals with 100lbs live rock, wet/dry, skimmer (filling up the collection cup in about 2-3 days with good coffee colored foam).  1 Rabbitfish in tank, who has pretty much eaten all the Caulerpa that hitchhiked on the LR. >>If the fish has eaten it, then there's little chance it's gone sexual. >My question is how do I get rid of the stuff?  Read lots of articles about how to prevent it, but none about how to get rid of it.  I've been running with activated carbon (yes, phosphate free) for a week now, no improvement.   >>Have you performed a few VERY large water changes?  That would be my FIRST move, as carbon tends to become saturated very quickly in a saltwater environment.  Then, I would CRANK up that skimmer, it's performing well for you, so just bump it up a notch along with water changes.  Also, I'd go for something like a Polyfilter before carbon, just in case you do have phosphorous present. >I was running 12 hours full light (with an extra hour before and after just running actinics).  I've dropped it (today) down to 8 hours (and no actinics).   >>The presence or lack thereof of actinic lighting will make little difference here.  Reducing the full spectrum photoperiod is a good idea, it just might give you enough bump, along with the large water changes, to get a handle on whatever nutrients the algae is fixing. >I did a 10% water change a couple of days ago. >>Pardon the phrase, but that is like pissing in the ocean.  50% or better.  I'd do 50%, three times, every day or every other day, and see what I get.   >Any other suggestions? >>If you haven't already, consider a refugium as well. >As to the source, I think it was overfeeding, plus I started using frozen Formula 2.  I defrosted it at room temp for about a half hour before feeding, so I figured that would work to keep phosphates low.  Am I wrong?   >>Well, I'm not really sure how defrosting would address phosphorous issues, I really don't think they're temperature dependent.  Overfeeding could be an issue, a balance must be found between ensuring your fish get plenty to eat and addressing nutrient export issues. >It is odd how the tank was fine until I used the Formula 2,  but once I get a phosphate test kit I will check source water too (I use RO from one of those aquarium Pharm-tap water conditioner tube things, thinking about going to a real RO/DI source, any suggestions?). >>I believe LifeReef makes good units, but I am not the best source of that particular information.  I suggest posing the question on our forum, http://www.wetwebfotos.com/talk  Also, do a search on our site for "Marine algae control". >Thanks in advance, Rob >>You're welcome.  Marina

Green Water & Caulerpa (1/19/04) Dear WWM Crew, I have been reading a lot on Caulerpa and its use in refugiums.  I understand why and how the Caulerpa can have a catastrophic outcome.  My question is once the Caulerpa has gone sexual and started to turn the water green, then what?  Is fish loss inevitable?? <Not necessarily.> Will the entire system need to be sterilized?? <No> Instead of me listing off a hundred questions, could you please list what steps need to be taken once this event takes place??  Thank You, so much!!  And I will certainly spread the word "Friends don't let friends buy Caulerpa"  Amen!! <There are still many who swear by Caulerpa (other than racemosa). There are ways of preventing crashing. These are abundantly discussed in the WWM FAQs on Caulerpa and other subjects. As for what to do if it is crashing, removing the dead stuff, performing large water changes and using PolyFilter and carbon will mitigate the consequences. If you are really worried about this possibility, then I would suggest Chaetomorpha instead.> Sincerely,  Jen Marshall <Hope this helps, Steve Allen>

Caulerpa going sexual, and lighting 2/12/04 Howdy. <Hiya> I have heard that if Caulerpa in a refugium is lit 24/7, it will not go sexual. Is this correct? <not exactly... it helps, but does not guarantee against it> Also, if I lit the refugium 24/7, would this have a negative effect on the pods and other micro fauna I am attempting to produce there? Thanks. <I think so. Its unnatural if nothing else. And it handicaps your ability to keep other/better macroalgae which will not tolerate 24/7 illumination (only Caulerpa does so). Do consider using Chaetomorpha or Gracilaria in your refugium instead. They are much safer and more stable by far. Anthony>

Reproducing Grape Caulerpa? Good afternoon, <cheers> I started out with a little clump of grape Caulerpa in my display tank. In a matter of months it has taken off into a ominous clump of algae that won't take no for an answer. <this is one of the things that makes this handsome macroalgae both a boon and a scourge> It looks pretty nice though, and has a great dark green color. I came home this morning and turned on the light to find that many portions of this plant had turned almost clear with a yellow tint. <yikes! Vegetative or sexual... dangerous (noxious and simply high volume organics/degradation. Be prepared with large water changes> Each of these portions were also spewing out a cloud of the same colored tint, and a lot of it! I assume these were only reproductive spores the plant was releasing. <rather common... and again, potentially dangerous. Do avoid this my actively thinning (never cut/prune... but simply thin friends ro reduce noxious exudations). This will interrupt its life cycle (4-6 months) and stave off such events>> I have never seen it do this before, and once the light was on for about a half hour the plant returned to normal as if nothing had happened. The clouds didn't seem to bother the fish much, but it did murk the water up pretty well. Heard of this before? <much has been written about this at length on the Internet, in hobby books (our "Reef Invertebrates" by Calfo and Fenner discusses this comprehensively), etc. Please do take the time to go to our home page at wetwebmedia.com and toggle key phrases (Caulerpa, sexual, vegetative, exudations, etc) in a Google search of our site with the tool provided (top left region of page)> Thanks very much for your response. ~ Stephanie <best of luck, Anthony>

The Crash (algae going sexual) My names Andrew and I'm a college student in LA. I'm doing a research project for my English class on the subject of Refugiums. <Man- all that we studied in college English was dangling participles, iambic pentameter- not even wet/dry filters...Man- things have changed!> I have done plenty of interest as I'm building one for my 75 gallon reef aquarium. What I'm asking is if you can recommend any sources or information on the Term; CRASHING. Crashing as in when the algae in the refugium turn sexual during the hours that light is not running over the refugium. If you could help, I would greatly appreciate it. Thank you for your time and thanks for having such a site. Its been very helpful in the past with my reef aquarium. Andrew <Well, Andrew, I'd start by doing a search of the FAQs on macroalgae on the WWM site, possibly using the word "crash" to see what comes up. Otherwise, you should investigate Caulerpa, which is often associated with "crashing"! Also, do check out Anthony Calfo's "Book of Coral Propagation" for more info on macroalgae and their use/abuse/benefits/pitfalls. Good luck!  Scott F.>

Caulerpa Bailout Hi, <Cheers, my dear. Anthony Calfo in your service> I was hoping you could help me, I have a 70 gallon salt water tank that has been up for about six months now. I use a Fluval 404 filter and a SeaClone Skimmer ( I know you don't like these but it was a gift and seems to be doing the trick).  <indeed...and agreed. Any skimmer that produces daily dark skimmate is a good skimmer!> There is about 60 pounds of live planted rock and about 2 inches of aggregate gravel ( I think that's what it is called?).  <do consider reducing or increasing this amount...more than 3" or less than 1/2 inch. The in between is a long term recipe for nuisance/disaster as it is not deep enough for denitrification, but too deep for thorough nitrification. If you'd like better nitrate control...have more than 3" of sugar-fine aragonite sand> I have a Sailfin tang, 1 coral beauty, 2 clown fish, 6 green Chromis, 1 scooter blenny, 1 orchid Dottyback, 1 canary wrasse, 1 cleaner wrasse, 1 carpet anemone and 1 bubble tip anemone as well as about 15 hermit crabs. <how long have both anemones been together... usually two different species that include on carpet don't last much longer than one year... the chemical allelopathy (silent chemical warfare) is too strong. The bubble will look fine one day and then mush out suddenly (days)> The tank has been running fine with only one outbreak of ich that the cleaner wrasse took care of in no time. The problem is when I turned the light off last night the tank was crystal clear but when I turned it on this morning the water was cloudy green and I could barely see into the tank. I have one large plant that all of a sudden died off yesterday, it turned white, and I removed that this morning. Could that be the problem??  <most certainly... it went vegetative/sexual...a problem with lush plant growth.> I did a quick water change this morning and another one this afternoon but the tank is still quite cloudy. The fish appear to be okay, but is there something else I should be doing?? HELP!! <the skimmer should be overflowing. if it is not, then it isn't working as good as you thought. Typically a good skimmer or two and a couple water changes settles the matter in three days. Little to be concerned about, other than the nutrients released by the plants possibly feeding a nuisance algae bloom in the near future...just keep an eye open for it> Thank you for your time and any help you can give me Chrissy <best regards, Anthony>

Refugium Bob, in a refugium with Caulerpa, why does the light need to be on for 24/7. <The 24/7 light cycle is supposed to keep the Caulerpa from going sexual.><<Doesn't always work... RMF>> Ii it because of slowing down growth or oxygen consumption? I would like to try 12 hours on 12 hours off. <If you do so, have the light on opposite your main tank. This way the Caulerpa is consuming the CO2 that your main tank inhabitants are producing at night.> Some of my Caulerpa seems to die off after a while and then come back. Thanks <No problem. -Steven Pro>

Re: My Aquarium Hi Bob I have been working on some of your suggestions and I just want to give you some feedback on what I managed to accomplish today (public holiday here in SA). 1. I added about 300 grams of activated carbon to my sump today - I couldn't find a proper bag to put this in, so I created my own bag with a piece of pantyhose, this bag of carbon is floating in one of the smaller compartments of my sump where the coral chips are. Does this sound like a proper adaptation of your suggestion ? <Yes... what we used to do... and folks still do... who have need of a large filter media bag... and a spare pantyhose about!> 2. Livestock - I added the following today: 4 x Turbo Snails 1 x Salarias fasciatus 1 x Cleaner Shrimp <Very nice> The fish are practically on their knees begging to be cleaned, but shrimp has been ignoring them until now and he has been in hiding since I've introduced him, but he just needs some time to acclimatize himself etc. <All will become "situated" soon> 3. Macro Algae - I managed to find some 'Caulerpa racemosa' today, a beautiful strand of green grapes, this is also floating in my sump at the moment. I have installed a 30watt fluorescent light above my sump for the Caulerpa. I have read all the WWM faq's I could find on Caulerpa and I have 3 questions for you about them that I am not very sure about - <Perfect> - Will the Caulerpa grow if it floats around in the water, or do I have to "anchor" it somehow at the bottom of the tank ? <Better to anchor... for now, a small piece of substrate gingerly laid over the distal end will hold it in place... give it pause to start spreading through rhizomes.> - With regards to trimming the Caulerpa I have found the following two suggestions in the WWM archives: <best not to cut it (saps colony, leaches undesirable elements, can cause die off of main colony, etc)... better to pull entire (unbroken if possible) out. Simply thin out the colony of convenient strands> <never cut Caulerpa and resist excessively breaking fronds as well. This leads to sapping and occasionally the dreaded vegetative events. Simply pull up unbroken continuous fronds (a little breaking is OK)> Maybe its just the language barrier, but I don't understand exactly what they mean by "thin out the colony of convenient strands" and "simply pull up unbroken continuous fronds". or would this become more apparent when I see the Caulerpa growing ? I haven't been able to find much about this on the internet. <This will be apparent. The strands are easily seen, either removed entirely as such or pinched/crushed if taken as a mass. In your application you will not likely encounter problems here> This is all I have managed to do so far, but I think I have taken some good steps towards my goal today. <Yes. Bastante. Bob F> Have a great weekend and thanks again for your helping me out. <Oh, will be out with friends diving, photographing in Mexico's Cozumel for a week starting tomorrow. Others here will gladly respond to your input. Be seeing you> Chris

Macro Algae Hello Bob, I just added some sand and placed Grape and Feather Caulerpa from my main tank to my sump, and use CP for lights. Well I noticed now 2 days later that my whole tank is very cloudy, and the Caulerpas are turning a light green almost white color. What has happened? Is the Caulerpa dying? Will the corals and fish in the main tank be ok? Please let me know if I'm in trouble. Thanks Rob <All should be fine... likely there is/was some die-off from the move, set-up... Do keep the lights on continuously to prevent reproduction... and of course a sharp eye on your water quality and livestock. Bob Fenner><<Bad answer... at least incomplete. I would carefully urge monitoring water quality, the behavior of the livestock... possibly moving the latter and cleaning/dumping most all the water here. RMF>>

Caulerpa Hello again, I¹ve told myself that I will try to stop sending you questions, but I keep thinking of more. I really appreciate your advice. My questions this time are about Caulerpa (grape) algae. I recently purchased some from Marine Depot Live. The rock came nicely covered in the algae (it also came with some Halimeda algae). The Caulerpa has now thinned out a lot. It turns white and appears to disintegrate. I have done some research about this and have talked with Marine Depot Live. Everything appears to point to the plant going ³sexual.² First off, I would like to know the details about this process. Could you give me some information about this? <Please read over the WetWebMedia.com site re macroalgae> My water quality parameters are: Temp.: 72-78s F pH: 8.0-8.5 SG: 1.0245 Ammonia: 0 Nitrite: .025 ppm (high, I know, currently working on this) Nitrate: 0-2 ppm Silicon: .3-.4 ppm silicon oxide (about .75 ppm silicon) Phosphate: Trace to nothing Calcium: 450-500 Alkalinity: At least 7 dKH The tank (a 40 gallon) receives sunlight (some direct) from about 8:00 until 4:00 and then is lit by 2x96w compact florescent lights (one actinic the other full spectrum) until about 10:30. No supplements are added to the aquarium. The algae is located about 16² from the light (directly underneath the full spectrum) and 4² from the front of the glass. Part of the algae appears to be growing and the Halimeda is doing good. Do you think that the sexual process is hurting the algae? <No> Should I remove the dead sections (most of my research says yes)? <I wouldn't at this point> Would you recommend leaving the lights on for 24 hours? <Not necessarily. RDP is fine, or just as you have. Bob Fenner> Thank you, Kevin

Caulerpa algae Hi Bob, a couple of questions about Caulerpa Algae. I just received the Feathered Caulerpa Algae from FFE it is about 10" tall and attached to live rock. My question is am I able to trim it aprox. 2" without killing it?  <Yes... do let it "get settled in" for a week or so from when you received it.> The other question is if a part of the Caulerpa is not rooted to the live rock will that hurt it? <No> Is there a way to root it to the live rock? <You can try gently waiting it there... but Caulerpa can, will attach where it deems necessary. Bob Fenner> Thanks