Live rock question hi Robert, I have newly discovered your site and find it very interesting and helpful. <Glad we have found each other> I am just starting up my saltwater tank and had a question for you. I'm hoping you can help me out on the problem of (and am not sure exactly what they are) but they're thin white almost transparent worm looking things that come out from my rocks and collect sand from the floor and make tunnels all over my rocks. Are these sweeper tentacles?  <Mmm, no. Usually called tentacular/feeding crowns. Of tubiculous (tube-building) sedentariate (they don't move about) polychaete (lots of bristles as opposed to oligochaetes "few bristles" like earthworms) annelids (segmented worms)...> Are they harmful? and if so, how do I get rid of them? <Not harmful, likely will pass on their own. More beneficial as filter feeders, food for your livestock. Just keep the viewing panels wiped clean of them and enjoy.> I hope you know what I'm talking about, thank you, Joe <Very common, no problem. Bob Fenner>

You've Got Worms! (12/07/03) Hey Guys, great website.  I had a question concerning new life in my tank.  I have a 12 gallon SW tank that I've had for one year now, and its been a happy year (knock on wood).  I have good purple algae coloration on much of my live rock, but lately a few new things have popped up.  There are small red bubbles, many with yellow tips forming on the purple algae, and some small red spot forming on other parts of the rocks. <Ooh. Sounds like a rash is saw on a kid in clinic last week. JK! It's a little hard to say without being able to see them. Could you send a good picture?> A darker, almost oily looking, purple spot has grown over some of the rock. <Could this be slime algae? Check pix in a good aquarium book or on WWM for comparison.> There are also some very skinny, brittle white tubes with strings coming out of them, that can reel in the strings at times. <These are certainly harmless mini featherduster worms. Fun to have/observe.> Lastly, there is a see thru tube shaped item, that looks like a long tube filled balloon, that is emersed in the rock, could this be an air bubble?  <If it is, it'll pop if jostled or touched. Again, hard to say much without looking.> Its almost metallic, very strange.  Anyway, I was wondering if any of these new "friends" were bad for my tank.  <If your water parameters are good and nothing appears to be damaged, I would not worry.> I do 1/4 water changes weekly.  Thanks a lot, Sincerely Jon

Bristleworm Good evening! <Steve> Please see attached photos (sorry about poor focus). This creepy-looking 4-inch bristle worm just crawled out of my 5-month old LR (80G reef) this evening. It gave me the willies at first, but now I think it's kinda cool. (I find the plethora of small organisms on LR to be every bit as fascinating as the fish in my tanks.)  Should I worry about this worm and remove it, or "can I keep him, Mommy?" Steve Allen <Same ole SOP reply... I would leave it be if it doesn't reproduce (not likely) or start chomping on (more) desirable invertebrates. Bob Fenner, sheesh>

Re: Bristleworm Bob: Thanks for looking at the bristle worm picture. Sorry for the panicked, silly question. I wasn't quite certain it was of the harmless variety and was a bit spooked by the size <Actually, there are no "harmless varieties"> I know the crew gets a lot of questions about these worms. Perhaps posting a brief "good worm/bad worm" topic with "criteria for removing worms" and pix of the nasty kind. One could even be more thorough with "LR Hitchhikers--the good, the bad, the ugly." If you would like, I could try to put something together using NMA-RI and "Reef Secrets" (among others) as references. Steve Allen. <Will we have to rub elbows with Clint Eastwood in a series of Italian/Spaghettios westerns? Bob F>

Something squirting out of my live rock. I've had my rock for a month now and I've noticed that two of them excrete some kind of slimy waste that comes out from the pores and disappears into the high current. what the heck is this?<You probably have some species of burrowing mollusks that inhabit the Live rock and they are stirring all of the sediment up within the rock, No worries here, IanB>

Amphipods on live rock - 9/05/03 Hello, Great website, I wish I would have found it sooner (have made lot's of mistakes).   I just received about 30# of Florida Aquacultured Live Rock tonight.  I put it my 75 gallon tank, where I plan to cure it (no fish). <fine>  After about an hour of placing the rock in the tank I noticed tiny whitish, bug like creatures crawling on the rock. <likely amphipods> They look like little elongated aphids, or something.  Are these mantis shrimp? <Not likely. More like natural lower food chain animals more inline with zooplankton. Check this out: http://www.nova.edu/ocean/jthomas/apod.html or http://www.museum.vic.gov.au/crust/amphigal.html>  Will they overtake my tank? <they could...... and this is a great problem to have. They will eat detritus, algae, and leftover foodstuffs.> One more, unrelated question (sorry).  I added couple of inches of crushed coral for my substrate.  Was this a mistake if I plan on this eventually being a reef tank, should I take it all out and replace it with sand? <Well, sand is natural and ideal. I have a 3 inch crushed coral substrate bed myself. I have had it for three years with a low occurrence of nitrate spiking. What ever looks good to you.> Thanks in advance for your expertise, <Our pleasure to serve you. -Paul>

<Tiny Worms> I have some white tiny worm like creatures all over my live rock, they resemble white hair on the rock work and sometimes on the glass. Are they parasitic and how do I get rid of them. I heard a six line wrasse? Thanks <Well, there are tons of little animals that come in on live rock, many (in fact, most) of which are perfectly harmless. Hard to say exactly what these may be, but it sounds like they are some kind of Bryozoans or Ectoprocts, or even a "peanut worm", all of which are harmless. Just keep observing the aquarium closely, stay on top of maintenance, and be sure to let us know if these animals get out of hand. Arm yourself with a good book, like Sprung and Delbeek's "The Reef Aquarium", which has descriptions and drawings of lots of "diversity animals" that can appear from live rock. Hang in there! Regards, Scott F>

White Puff Balls on LR My wife and I, both novices, are into our 11th month with our new reef tank when we noticed a white, cotton like, puff ball growing under/onto part of a live rock.  When we asked our fish store expert about it he suggested it may be a type of "Tunicate" and told us  not to worry and also gave us your web site address.<I too have had this mysterious white stuff on my LR...I believe it may be some type of sponge (angelfish loved it).  Going through some "FAQ'S" I noticed one hobbyist said he found some "white puff balls" on his bio balls in his filtration system but there was no explanation as to what they were in the conversation.  Can you enlighten us as to what this is? <A picture would help greatly>  It started out small, about the size of an M&M, and now it is close to 3/4's the size of a ping pong ball.<again, I believe it maybe a species of sponge>  It is not exactly round and has very small black specks, like pepper, on the exterior of its' body.  I appreciate any help you can provide.  Thanks.<your welcome, IanB>

Re: White Puff Balls 5/23/03 Thanks Ian. <Anthony Calfo with the follow up... Ian is quite likely correct. And specifically they are Syconoid sponges of the genus "Sycon". Very common. Use these names for a google search of our archives... some of the FAQ pages have pics to comare to. Kind regards to all>

Unknown creatures in the water!  (6/20/03) <Hello! Cody here today!> I recently purchased some live rock. Now I have small creatures, numbering in the hundreds, crawling in and out of my substrate, live rock, and everywhere else then can get to.  They are a little bigger then a mosquito. They have a very long "tail?" and scurry around at knight.   It looks like they are effecting the live rock but I'm not sure.<At first they just sounded like harmless copepods but if they are affecting the live rock they may be something different.  Let me know how they are effecting the rock and a picture would be great.  Cody>                                     Help!                                         Thanks,                                                Kevin

Re: small unknowns in the water (6/22/03) Thank you for the info. You are right . I found a picture of one type. It's the same. As for the live rock, I don't see the different growths that it had when I bought it. I'm not sure what is going on. <Many things will die off and grow over the years which is one of the most interesting things about live rock.  I've even heard of octopuses emerging after months of the rock being in the tank. Cody> Again, thank you, Kevin

What's this stuff on my live rock? >Marina~ >>Yes, Steve? >I have a question for you concerning my live rock.  It looks like there is some small whitish looking fluffy stuff starting to grow on it.  It looks like it is starting to grow on the rocks that already have coralline on them.  It also looks like little white globs of it, the almost look fluffy.  Any ideas? >>Tunicates?  Or...?  Any pics?  I'm not too good with the ID stuff of unknowns, but we now have one brilliant Chris Maupin who might be able to help out.

Something drilling into live rock - 9/4/03 Our tank has been set up for about 6 years and recently we noticed a couple of live rocks being "drilled" into...<Hmmmmm.> We can see the hole and also grit and sand under it. <Hmmmm.....have you done a visual with the lights out?>  I have not had any luck looking up into the holes or seeing what is causing it. <Keep trying. You're bound to catch the guilty party>  Should I be concerned? <Have you added any livestock or rock recently?> Our fish are all healthy but a clam died over night after being healthy the day before. <Interesting. Any "drilling" on the shell? Postmortem report?>  The other clam which is much larger is doing great still. <Keep an eye.>  All  levels check out great. <Very good.>  It could be coincidence that we lost the clam <Actually, very possible. Clams have been known to crash for various reasons from starvation to fluctuating chemistry> but I am curious to find out what is making a home in my rock after all these years. <There are a great many creatures that could do such damage to live rock. More than likely something that either utilizes some type of algae for nutrition but could just as easily be something eating your zooplankton (mine hide in little caves in my liverock). Also, I have been hearing of liverock dissolving over time as well. This is likely not an issue your encountering but....well.....something o think about. Frequently check when lights are out, but unfortunately, I can offer little help without more information. Please keep me informed and updated on the goings on. Good luck. -Paul>                             Thank You for your time                                    Heather Gosling

-Atlantic live rock hitch-hiker- I recently purchased a 10lb live rock (Atlantic aqua cultured) which seemed to relatively sparse of life. As with all live rock, there are some things that weren't present at first now showing themselves. I have a question about this one because I have not seen anything in my two months of reading that indicates what this might be. So my best to describe it to you since I don't think I can get a decent picture. <ok> It appears to have very long tentacles, which stretch out from a central point at the base of the rock. These tentacles are a pink/salmon color, and have no visible cilia. The tentacles are thinner at their outward ends, and slightly thicker at the base. They seem to move around, expand and contract, and are responsive to light. These tentacles are very thin in comparison to their length, some appear to be 8 inches or more in length with no more than 1/10th an inch in diameter at the base. <I'd wager that it's a polychaete commonly called a spaghetti worm. You'd notice that it can reach out for a small piece of food, then reel it in with one or more of its arms> I understand that in the future I should quarantine any life form to be introduced into my tank, but I am at a very early stage (started just over a month ago) and have been just placing the rocks into a bare tank. I have no fish, only one coral and three crabs, all of which were additions made with live rock. I am concerned with this particular item because it is able to reach out so far. If it is a stinging celled animal, I am not sure what kind, or what to do to eliminate it if that is the best course of action. <No need to worry, completely harmless and beneficial> As always any information you can provide is very much appreciated! John <Good luck! -Kevin>

-Live rock hitch-hiking corals- WWM crew!!!! <Kevin here> Thanks again for the tremendous knowledge you guys give on this site and also in your books. Your knowledge and advise have yet to be matched. So once again thank you. <On behalf of the entire crew, you are very welcome!> I have a 120 gallon reef tank with 84 lbs. of Kaelini rock, 30 lbs. of Fiji rock, and aprox. 12 lbs. of Tonga rock. Live sand with 17 hermit crabs and 10 Turbo snails. I am running a Cascade 1500 <Never heard of this one...> filter and 2 CPR BakPak 2 protein skimmers. 1 maxi-jet 900 and 3 maxi-jet 1200's for water movement. My lighting consists of a 48" Custom Sealife Power compact. 2 10,000K daylights, 2 ultra antic, and 4 moonlights (very cool looking if I do say so myself). Also I am almost obsessive compulsive with the water changes so the water quality is good by most standards. I have tons of questions however I will limit it to 1 tonight as it is getting late. On a piece on the first piece of Fiji rock I put in the tank looks what appears to be a very small Xenia stalk is this possible?? I know anything is possible. <Yep, anything's possible, but I doubt that xenia could survive the vigor's that rock goes through as they can barely survive being shipped normally> But I am curious as to how. Was is seeded in the rock along time ago and survived the trip to my humble abode. Or is it a natural occurrence that comes with perfect water conditions?? <They ruled out spontaneous generation a long time ago, so it definitely came with your rock. Some coral can survive the journey on dry live rock quite well and blossom into large colonies once established. Without a picture I care not to guess what it is, but if everything goes as expected, it should take off in no time. Good luck! -Kevin> Thanks for all you do ~~Jason~~

LR-critters In my 45 gallon, 45Lb Fiji LR, 45 Lb live sand tank, I have a serious cleanup crew, 2 Pepp. shrimp, 1 emerald crab, 2 chocolate chip stars, 2 false clowns, and 1 queen conch...I have noticed a coupe snails...who have stayed alive, and not placed by me in the system.  they are growing and one is roughly up to about 2 mm in length... guestimate!  They are 2 toned striped lightish brown/khaki with the other stripe being a little darker brown. <probably a Nassarius species>   They make their way around the rock and sand...mostly rock.  Any ideas?  The other things I am trying to ID might be a little tougher.  I find them mostly floating on the top of the tank, and don't seem alive.  The are small maybe 1 mm long tubular things that from afar look like worm segments.  Up closer they look tubular still...but...one side of them looks transparent, and they other much darker and opaque. The transparent end almost looks like a tail, and comes to a point...while the darker end is more rounded.  It has equidistant segments to it...with microscopic points (seem under magnifying glass) coming out of the side in am almost flat tubular body(?) shape.  they crunch and flatten when squeezed between fingers (exoskeleton?)...nothing in the tank eats them to the best of my knowledge...and like I said are mostly found floating.  I have tried to be as descriptive as possible, and hope you can help!  Steve <well these just sound like helpful organisms that come along with the LR... no worries my friend, IanB>

Assorted Reef Growths - 8/13/03 Hello Bob! I've not spoken with you in some time. Hope all is well as can be with you. <Anthony Calfo in his stead... Bob is right now sun-tanning nude in Indonesia as we speak> I went back to college and already knocked out two semesters (4.0, no less - better than last time). Am working on a masters of science in applied history and a degree in geology. Hope to teach at the college level then move on to museum/archive mgt./document work, etc. <kudos... onward and upward> But...still fishin' as well. Question: I just brought home some of the most awesome Tonga live rock. It is in the final curing stage. Two things I'm not sure about.....1) forams; Homotrema rubrum. What are they? Got lots of 'em. <they are simple protozoans... related to amoebas... harmless filter-feeders. Do enjoy> 2) I have a lime green calcareous growth that is spread like coralline; is that what it is? Sure looks that way. It's gorgeous mixed in with the red, purple and pink. Could be sponge(?) <We could not say without a pic and better description of behavior, texture, visage, etc> This is the 46 Oceanic bow. 40 lbs. of Samoan white sand and 42 lbs. of the Tonga rock. Will house more tame species - six-line wrasse, orchid dotty, a blenny, a goby or two, Chromis, a clown, and the usual assorted crusties. Regards, from  David A. Bell <best regards, Anthony>

New Occupant in LR Tank Hi Bob, Steve, Anthony and all others - Can you identify this critter for me? It's roundish, about 1" long, and has a long white proboscis that will protrude quite a distance, curl and twist, and can be retracted at will. I am assuming it's some kind of worm, but don't know if he's a good guy or should be removed. <Likely your creature is fine, but your best bet for identification is to work your way through Dr. Shimek's Dichotomous Key here http://www.rshimek.com/Invertebrate%20Key%20to%20Major%20Taxa.htm> Thanks again for your help, Connie <You are welcome. -Steven Pro>

Identify Some Species? Hi there WWM Crew. <Howdy> I was wondering if you could identify some critters that started growing on my live rock. The rock is about 2 years old. <Will give it a go.> The first ones I am interested in are the small white tube-like bodies with the bright orange fan-shaped mouths. I have just seen these things for the first time this week. These guys are small, the tubes are about one-eight inch diameter. See the middle of the picture, below. Any comments on desirability? Should I try to eliminate them, and if so, how? <Mmm, this picture didn't come to us... but these are likely some species of tubiculous (tube-dwelling, building) polychaete worm... I'd leave them be> The second critter is the species of feather duster below. I see from WWM that this is an Hawaiian species. I have hundreds of these in my tank (and overflow and sump) that seem to have seeded themselves from the rock about a year ago. Desirability? <Uhh, these are Aiptasia Anemones... undesirable. Please see here: http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/aiptasia/aiptasia.htm and the associated (linked) FAQs files> The third thing (critter?) is the white fuzzy growth shown below. This also was just noticed about a week ago. Problem? <This is likely some sort of Syconoid sponge... no worries unless the overall quality of your system sinks so low that it covers over everything. Bob Fenner>

LR Freebies I have about 60 pounds of Live rock in my marine aquarium and it's doing great.  It's been in there for about 8 months now and really taken off.  I have noticed a lot of interesting growth on the rocks in places.  There are some sponges (which I have removed except for a few interesting ones) but I also think I'm seeing some corals forming.  is this possible?  They look like small polyps and such.  I have no other corals in this tank right now, just live rock and marine fish.  Is it uncommon to have corals grow from live rock or am I seeing things?  Just wondering. <It is indeed possible for corals to "just happen" from even what appears to mostly dead, old live rock. What a planet eh? I'm not leaving! Bob Fenner> John

Hitchhiker id: Hello "Crew" - <Hello, Ananda here...> Love your site. <Good to hear!> I can usually find answers to my questions within your site, but haven't found anything on a hitchhiker I recently discovered on a small piece of live rock. <Lots of stuff to be found on live rock....> 10 gallon tank 1 small percula 12 lbs. Fiji rock purple mushroom yellow polyp some green zoanthids <Sounds like a nice nano setup.> I'd send a photo, but the creature in question is tiny, so I'll try to describe them to my fullest. On one piece of my live rock there seem to be some type of tube builder/dweller. Protruding from each tube (each tube is only about 1 mm in diameter) are 2 tentacles which are transparent and can stretch to over 2 inches (tentacles are maybe .5 mm each) which don't seem to have mouths or a head so I don't think it is something like a bristleworm or such. While observing, the tentacles just seem to wriggle around on the outside of the live rock, but now they have constructed tube-like structures made out of sand grains attached to the rock over their dwelling holes. None of the zoanthids on the rock seem to be irritated by these little tentacles which (the tentacles) retract upon disturbance. <It's a common spaghetti worm -- though I think vermicelli worm might be a more accurate common name. Nothing to be worried about. There's a pic here: http://www.wetwebmedia.com/polychaetes.htm> Have you seen/heard of such a thing before? <Many times.> Thanks for any input you can provide. Sincerely, Chris <You're welcome. --Ananda>

Reef Dust Hello everyone ! <Greetings> Have some questions again so your wisdom is needed ! I have send many e-mail in the past (reef on a remote Greek island!!!) I finally got some living organisms for my tank. I have the fish in quarantine Of course, and in the main tank I added three polyps, three mushrooms, and three father dusters. Everything is doing very well (polyps are fully open ) except one mushroom. It has a green colour and although most of the polyps are open the middle part of it, at the centre of the rock did not open since the beginning. Today I found it covered in some white membrane (milk like) and when I tried to touch it with the clams it just turned into particles. The membrane disintegrated as well as the polyp underneath in that area. Is it a king of disease? What should I do ? <Not a disease. Likely just a remnant of a feeding mechanism. I would not worry about this. Bob Fenner> Take care   Kostas

What was THAT?? Hi WWM friends. Today as I walked by my FOWLR tank I happened to catch a glimpse of something being ejected OUT of my live rock. It was wispy, very much like cigarette smoke. It came squirting out and dissipated into the water. Any ideas??  <yep> Somebody in there spawning maybe?  <possible... but not likely> It was freaky. Hope it doesn't hurt the tank. Wes <no worries... there are many burrowing organisms in live rock: boring clams, urchins and more. Somebody was simply mining a bigger or better home. Enjoy the diversity>

Unidentified Tentacles Hi Bob- <Steven Pro in this morning.> My reef tank has been up and going for four months now. Everything looks like it's doing well, although I have had to kill three Aiptasia (with Kalkwasser injection), including two recently. <It happens.> I was warned and have tried to keep a careful lookout for them. My question is this, lately I can see two or three or four long thin tentacles coming up from the live rock under one of my corals. These tentacles look like strands of a web - they're not even as thick as a cleaner shrimp's antenna, and seem to be a clearish color with dark thin stripes, as best I can tell. They can extend to at least 4 inches long, and as they wave around in the water (it does seem like they control their movement to some degree) they may be stinging the coral above them - the xenia-like polyps seem disturbed and curl up somewhat after contact, but I can't see any measurable damage. When I moved the coral and tried to figure out what I was dealing with and where it was coming from, the tentacles retreated into or below the rock. <It sounds like a spaghetti worm to me. I would work your way through Dr. Shimek's Dichotomous Key to be sure, http://www.rshimek.com/Invertebrate%20Key%20to%20Major%20Taxa.htm> I'm concerned that this could be another Aiptasia, <Not likely> although I've never seen Aiptasia extend tentacles like that, or maybe something else harmful. <Actually, most liverock hitchhikers are harmless to beneficial. There are a few exceptions like the Aiptasia, but by in large most you find are fine.> I'd really rather not start pulling my tank apart to figure it out or kill it if I don't have to. Any ideas? <See above.> Thanks, Bob, and please hit Reply All if possible. Brad <No problem. -Steven Pro>

Stuff on my live rock! <<Greetings, JasonC here...>> Well, I guess it isn't really "stuff" on my rock, it looks more like "things" now that I think about it. I noticed two or three or them a couple of weeks ago and now there are about 200 of them. They look like tiny(1-5mm) tubes of cotton that have "featherduster like" openings at the tip. when I look closely I can see that they are hollow in the middle. The rock that they are on have been in the tank for about six months (Since the tank has been up) but none of the others. Any idea of what they are or how to get rid of them? <<Could be any number of things, but I wouldn't be in a hurry to get rid of them if I were you. They are most likely an unique type of snail called a Vermetid - they don't move, but do produce strands of mucus which they use to trap 'stuff' and reel it back in for dinner. Pretty much harmless.>> I didn't add any fish or corals around the time I found them, but have been adding rocks. Please share your knowledge and expertise with the rest of the world, and rid my tank of these "things"!!! <<Why should you be rid of them? Most of these items are not only harmless, but also useful in the grand scheme of things - part of the "system" which is coming of age in your tank. I would sit back and enjoy it. Cheers, J -- >>

New live rock filaments Hi, Long time listener, first time caller. <<Hi Mark, Thanks! The ratings are up!>> Last weekend I started converting my 55g F/O tank to a fish and live rock tank with 70lbs of live rock that was fully cured, but very full of life. There are all sorts of beautiful and varied macro and coralline algae. It seems to be in great shape (I drove it home from Harbor Aquatics myself and kept it in tubs) and I've seen only an almost imperceptible spike in ammonia which has started to subside already. I moved my four little fish to a separate tank while waiting for the tank to stabilize.  I've spent hours and hours observing all of the little critters and growth on the rock but one thing I've noticed is a decent size population of some sort of organism with a very impressive filament. They're not tube worms - I have found a few of those and these are definitely not them. In fact, it's really hard to tell what the organism is because it grows on top of the algae or right on the rock itself. It's very small, sometimes making a lump or mound less than a millimeter high, but the filaments are HUGE. I've seen some that are easily four inches long. They appear to be single stranded with very geometrically spaced branches usually off of a single side (like a feather). The filament shoots out into the water for 5 to 30 seconds and then gets pulled back in. And, they don't appear to be out at all times. When I feed in the morning, they're already out, but my wife says they disappear for most of the day. Then around 4:30 or 5:00 in the evening they start appearing again and stay out 'til lights out. Any idea what they might be? I hope it's nothing to worry about because they're awfully impressive and fun to observe. Thanks. -Mark <<Live rock comes with all kinds of life on it *intentionally* that's why it's "live". Most of them are difficult to identify without a photo, and even at that ID may be difficult or incorrect. Almost all of them, with few exceptions are harmless and enjoyable, even beneficial. You might try :http://www.tcnj.edu/~maughme2/faq.htm http://www.rshimek.com/animal_identifications1.htm and see if you can't ID them here.>> <<Have Fun! Craig>>

New live rock; invert id To the wet web media crew, I recently picked up some uncured/base live rock from my LFS. I was expecting white pieces of rock but once I picked it up, it looked magnificent. Plus, it was very cheap, and also teeming with life. The calcareous algae look great. There are a few wanted and unwanted organisms on it. This rock will eventually go into a fish only tank once it is done cycling. As far as the good life goes, aside from algae, there are two different types of feather dusters, black coral polyps, small white/tan starfish (which might be good or not?), an interesting crab, and probably countless others I haven't seen. This crab is of interest to me. It has a "typical" marine crab body shape. If I had to pick a look-a-like, I'd say it has the body shape of an emerald crab. It's main carapace is a deep purple to brown and its legs are white/tan. Its legs, however, are very hairy. It really looks like a tarantula. It does a very good job of hiding all day long. It is currently enclosed in a critter keeper until I can determine its risk to my small fish. I haven't been able to identify it yet. <I wouldn't worry unless he is large enough to fish... Keep an eye out but if he's small not a current problem.> On the ugly side of things, I have a few contenders. Aiptasia are everywhere and I'm slowly eradicating them. There are also a few unidentified things I thought you might know of. I dropped in some very crushed up flake food and all sorts of life came out. One is a small tan worm with lots of legs all around the body. It was only about 2mm long. I'm guessing it is a species of bristle worm. Are these dangerous to a FOWLR tank? <Get the Aiptasia. Leave the worms. He revealed his intention....to eat the extra food you leave around. (that's good!)> Now, this one is the real reason I'm writing this e-mail. Upon return after dropping in the food, I noticed what I thought to be a string about 8-12 inches long. It was maroon and I thought I had dropped it in there on accident. Using a pen cap, I lifted the string and pulled it out of the water. It definitely didn't look like a string at this point. I let it go back in the water and it drew back into the pile of live rock. This thing was pretty freaky. Any idea at all what it could have been attached to on the other end? <A type of spaghetti worm or? Hard to ID w/O a photo, and maybe not then! Don't worry, that's why we buy live rock! Most of these things are completely harmless. And entertaining!> I'm guessing that the unidentified star is harmless to fish only until it reached a big enough size it could be removed. <Yes. Or eats something you like that doesn't move.> If you have any ideas or suggestions, I'd be interested in hearing them. That "tentacle" thing was really weird. Thanks, Dave <Just enjoy the wonder Dave! Craig>

White "coiled" worms on glass Hey guys, I have a question regarding small, white, coiled worms that are all over my glass and live rock. I have heard that they are common in a new tank and that they should go away on their own. My tank has been up for about five months, (all parameters are good) but these coiled worms are spreading everywhere, I scrape them off the glass, but they are beginning to look very ugly on my live rock. The live rock has very pretty red and purple coralline algae covering most of it, but everywhere else these worms are spreading. Is there anything I can do to get rid of them? Is it possible that the worms could grow over the coralline and eventually cause it to die off?  Thank you for your help! Derrick <Not to worry Derrick, they will limit out on their own. They won't cover everything. They are part of your live environment, enjoy the wonder and give your tank time to establish itself. Five months in ocean time is about a billionth of a nano-second. You will find there is really very little horrible stuff to worry about. Craig>

Hard white wormy things Hi Bob and co-fish advisors- I have some strange things appearing on my live rock and they look like white worms. They are calcified and I don't know what they are. At first I thought they were feces from Bob our dwarf angelfish, but it's in both tanks. I have tried scraping this stuff off and it takes the rock with it. Do you know what it is and how I can prevent it from spreading/reoccurring, and do you know how I can get rid of it? <they are harmless/beneficial Vermetid worms or sessile snails (snails that build a worm like tube in place and filter feed). Inevitable in most healthy marine aquaria. There is no reef-safe method of control (all such will harm live rock or other desirables). Simply keep up with scraping them from the front glass. The best way to temper them (at the risk of other wanted filter feeders in the tank) is aggressive filtration and skimming> Thanks to you all, Connie Cavan <best regards, Anthony>

Micro-organisms from Live rock I have a very big problem with my tank! I have these white puffy balls all over my live rock, my wet dry, glass, in my skimmer and  they seem to be multiplying like crazy!! Just imagine a bright white puffy ball with a white featherduster protruding through the center. <these are Syconoid sponges and are helpful to water quality (filter feeders). Their population is exploding because you have a nutrient export problem in the aquarium. Overfeeding, lack of water changes, lack of a good skimmer (producing dark, daily skimmate), etc). Reduce the nutrients and the sponges will wane too> At first it was not really bad , but now I have these little flea like creatures all over my tank <they are natural plankton. Copepods and/or amphipods... they are also a benefit to the system: food for fishes and invertebrates. They also thrive when there are high nutrients. Do examine your maintenance and feeding habits> About 40 balls and hundreds of fleas which are also white. What do I do? <improve water quality and enjoy all that remain. best regards, Anthony>

Mystery Polyp  Hi guys, Thanks for so much help, here's another one for you. I was checking on my fish after the powerhead gave out and noticed that I have some new inhabitants.  I found a young brittle star about 1.5 cm across and two which I believe to be polyps.   <very cool!> These guys are huge, the one in this picture is about 3 cm across.  Any idea what it is?   <alas... it is not clear enough from the image. Does not appear to be stony, though. Perhaps anemone in nature> I never bought them, they just kind of popped up today.  Thanks, Rene <and you will discover so many more things in time as the rock and sand mature. So many more things are never seen unless you peep at night. Wait several months and then sneak up on the tank with a flashlight filtered through red cellophane. 3-4 hours after the tank has been pitch black... peep with the flashlight and see many wondrous denizens of the night! Enjoy. Anthony>

Unidentifiable Creature from my live rock Hello I've e mailed a couple of times. Our live rock has been in our tank for 4 days now and last night we noticed a bunch of tiny "bug looking" things swimming around on crawling around on the glass. We were excited to see some form of life, but not sure what they are. Then this morning we checked the protein skimmer and found two bigger forms of these tiny bug looking things. They almost look like brine shrimp or something. They're no bigger than 2 mm, they were digging in the scum in the skimmer to hide from us. What do you think these are?? <They sound like amphipods and copepods.> I'm assuming that the tiny ones are babies?? <Not necessarily. If they appear the same but smaller then yes, but quite likely you have several different kinds of critters.> Will this be good food for the fish when we finally put them in? <Yes> The cycle is just starting. Ammonia 0.25, Nitrate 0.25 and nitrite 5 pH 8.2 Sp. Grav. 1.023. It's been 4 days since we added the live rock. We've been only turning on our lights (one 40 watt actinic bulb and one 40 watt regular) for 2 hours a day per your book. Is this OK?? <This is fine. When the cycle is complete, increase lighting to a normal day long photoperiod (8-12 hours).> Should we do our first water change?? The water has been in for 6 days and the rock for 4. How often should we do water changes while its just live rock? <This will depend on your ammonia and nitrite readings. You do not want to allow them to get high enough to damage the life on the liverock.> We're planning on cycling our 10 gal quarantine tank with 2 damsels which we'll get in a few days. <Why not just hook up the quarantine tank filter to the main tank while it is cycling?> How often do we need to change the water on the quarantine tank? <When housing fish, I like to change a small amount daily, 1-2 gallons. When you remove the fish to go into the main display, drain the whole thing and refill.> One more question. Do we need to put substrate in our quarantine tank? <No substrate but a hiding spot or two made of inert material.>> I can't find any info in your book. Right now we just have a piece of PVC pipe and the water. <That will be fine.> Thanks for your help again. Katie <You are welcome. -Steven Pro>

Creature ID Hi all, <<Greetings, Wes.>> I was hoping you might help me id a critter that came with my new Fiji live rock....let's see if I can describe this because I can't seem to get a decent picture of it....imagine a 1/3 inch, whitish, hollow cigar sticking straight off of the rock. It has a short stiff ring of "feathers" similar to a feather duster at the very top. The feathers do not retract. It's body (the tube) is quite fuzzy with single "hairs" protruding perpendicular from it's sides all around. Basically it looks like a small, but fat, fuzzy tube with hairs and a stiff crown of feathers. How's that? Need a picture? I will keep trying but my digital doesn't focus that close up... <<You are right, that's a toughie without a photo... did you try your luck here? http://www.tcnj.edu/~maughme2/faq.htm If you get a clear photo, send it along and I'll try again.>> Wes <<Cheers, J -- >>

Pest Problem? Thanks for the advice the other week on cycling of my tank Bob. I have one more question. It seems the cycling is progressing - up to nitrite now. The problem is I seem to have an infestation of pin head or smaller sized white creatures jumping all over the live rock. What are they and how do I get rid of them. <They are amphipods or copepods and you do not want to get rid of them. They are an excellent natural food.> Currently there is only live rock in the tank. I am assuming they arrived with it. They seem to stick quite close to it and also on the glass. Many Thanks, Brett Moloney Brisbane, Australia <You are welcome. -Steven Pro>

Night Crawlers and other LR phenomena I was looking in the tank tonight with a flashlight to see what popped up, and there were a few surprises. First, one of the live rocks has got tentacles coming out of it--about 2" long, and banded (lighter and darker "rings" around them). They retract on any motion. There are about 3 tentacles coming out--looks pretty eerie. There doesn't appear to be any central body, like Aiptasia, just the tentacles coming out of the holes in the rock (from several different holes in the same general location on the same rock). [The tentacles actually are pretty near the hammer coral. Am I in for a "stinging war" of sorts here?] <Likely not> The second thing I saw was a small crab--his shell is about 1/4" to 1/2" across, and is white/off-white. Proportionately, his symmetrical claws are very heavy (as compared to his body, they are of considerable mass) and are also white/off-white. However, his legs are sand colored, so that when he's on a rock, you don't notice him unless he moves--because with the darker-colored legs, all you see is his body, which looks like a small pebble. Thought you might have some ideas on what these night crawlers might be. <All sorts, but nothing definite> I'm READY for the calc reactor--I can't seem to get my calc above 340-360 with the additives, and it's really messing up the tank, clogging the filters and leaving residue all over everything. . . However, the BGA (black slime) that had been growing on the rock where I had been putting in the calcium has all been consumed by a small, hungry sand goby that was added last weekend along with the maroon clown. That goby is worth it's weight in gold--he hasn't stopped filtering sand since he got here, and the substrate is getting much cleaner as well. <Ah good> P.S. I did find another Aiptasia today--on a "base rock" that really can't be removed and soaked. The Aiptasia haven't reappeared on the rocks that got soaked in freshwater. I may just leave this one be and add a predator later if it seems to be spreading, unless I should try to stamp it out now before it gets out of hand. (I guess my question here is, can this stuff "explode" and infest the tank rapidly, or can I observe it for a while with no significant risk of infestation?) <Who knows? Perhaps.> Hope you're having a nice weekend. No crisis this time--just a couple of inquiries. Thanks for your input! --James Deets <Be chatting. Bob Fenner>

Unknown Life form Hi Bob, My 92 gal. is about 3 mos. old now. My Walt Smith Precured Live rock purchased at FFExpress is about one month old. This morning when I turned my lights on I saw something that looked like a little critter of some kind scurry into a hiding hole.  <All sorts of surprises...> It was a milky white color and it was scurrying on the rock, not swimming. It was maybe 1/4 inch in length. Have any idea what this is and should I be freaking out or what?  <No real worries here... likely a species of amphipod... a sizable group of small crustaceans... of more use than harm at any length... but all-too often consumed in ongoing systems> I checked as many FAQ's at FF and WetWebMedia that I could but I didn't see anything that looked like this little guy. <Thanks for this... need to develop (or find someone's URL to refer to) with lots of the "common" mystery items like this...> I appreciate any suggestions you might have on what I should do now. I have 2 yellowtail blue damsels, one domino and a scooter blenny. I would like to add some more livestock but I don't know if I should be worried about this "thing" or not.  <Not to worry... accept about being bitten by that Domino as it gets larger...> OH one more thing...I have (had?) a feather duster that is attached to the rock that the alien scurried into. The feather duster lost its' top and the tube is still standing there. I read that it could be growing another, is that right?  <Yes, typically> Thanks for your help....I read your site so much I feel like we are friends! I like your bio, too you're a cutie pie! Thanks again, Joyce <Ah, a delight. Bob Fenner>

Magical Mystery Worms/Rock Hi Bob, Hope you are/did enjoy your visit to Asia. <Oh yes> I checked throughout WWM but didn't find anything that really addressed a question I have. I was doing a little rearranging in my reef tank tonight and came across a couple of "somethings" that were a bit unusual. I suspect they are some form of polychaete/Serpulidae worm, but was hoping to get some confirmation. The first one appears to be calcareous tube of a wine color with ridges or segments a la an earthworms body. It has a beginning diameter of @ 1/8" growing to @ 1/4" via an erratic counterclockwise spiral. I did not see any evidence of the builder. The second one also appears to be calcareous tube. This one does not have ridges, but rather periodic protrusions similar to the dorsal plates of a stegosaurus. It is an ivory color with a beginning diameter of @ 1/16" growing in a counterclockwise spiral up to about 1/8". There appears to be a red colored creature in the tube. Neither of them appear to display the crown that I, in my layman's view, consider "typical" of polychaete worms. Any thoughts on what these beasties may be? Thanks as always for your help, Mike <Agree with your overall assessment... "some type of tubiculous worms", though perhaps encrusting mollusks... and likely no worries. Bob Fenner>

Worms in the rock? Bob, I have a 45 gallon saltwater tank with all of the proper equipment. My problem is I bought live rock about 20lbs. of it about 3 months ago and now I am noticing something strange. It seems one of my live rocks is deteriorating and I also see these transparent type of worms coming in and out of the live rock. are these creature dangerous for my tank? Will affect my existing fish, I have a yellow tang, strawberry gamma, false percula clownfish and some invertebrate? <Well, good live rock is highly perforated... but already coming apart? Have you contacted the outfit that sold it to you? Most "worms" (there are thousands of species) are innocuous... I wouldn't panic at this point unless these ones get way big, too numerous. Bob Fenner>

LR Identifications Dear WWMCrew: <Hi there> I've attached two pictures.  These are of things that came on Florida aquacultured live rock. <I see> The first picture is of a purple bushy thing. We have two of these, and one is placed close to the light, the other far from the light.  Both appear to be dying (they were shipped to us only a week ago).  Could this be a type of sponge, and we need to get them out before they pollute the tank too much? <Not likely a sponge... but could be. Looks to be an algae. I wouldn't worry about it> The second picture shows a horn shaped creature with alternating maroon and cream colored "pie slices" on the horn viewed from the front.  If you look closely, you also see small tentacle-like things on the horn, especially around the edge. <Yep. Some sort of polypoid animal... maybe an anemone...> The second picture also shows what appears to be a small anemone, tan with a little white.  It's harder to see in this picture, but if you had a guess about it's identity that would be welcome too. <Can't do... too small, obscure> The live rock also has some corals, which I assume are stony corals.  They appear to have survived shipment and their polyps have opened up after a few days in the tank.  How can I tell if they're doing OK? <They are... as they appear to have survived the rigors of collection, processing, shipping... and so much life is... part of your shipment. Enjoy it... as this and much more will unfold, supplant, be supplanted by other forms in time. Bob Fenner> Thanks. Tom

Re: Identifications Thanks, Bob. <Welcome> It's fun to get a reply from you, though I can't complain about the helpful previous exchanges I've had with others on your crew. <Good to hear/read> Since my son and I started this project with naivet?and three books (one yours) last June, common refrains in this household include ... "Fenner says ...", "According to Fenner ...", "What does Fenner say about that?".  Yours became the book we most trust. <Around here it's "That knucklehead said what? Just get back to 1) vacuuming, 2) making meals, 3) writing..." Do you have a recommendation of a good fieldguide to invertebrate life in the Caribbean? <Oh yes! The best bar none is Humann, Paul and Ned DeLoach's wonderful series "Caribbean ... Guides"... you can find these most anyplace... maybe take a look on seachallengers.com re>   I'd like one good enough to identify these creatures that we continue to find on the live rock. <Is fun, never-ending source of wonder. Be chatting, Bob Fenner>