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FAQs about Live Rock Hitchhiker/Creature Identification 7

Related Articles: Live RockReef Systems, Refugiums

Related FAQs: Live Rock, Answering Some LR FAQs by James Fatherree, LR Hitchhiker ID 1, LR Hitchhiker ID 2, LR Hitchhiker ID 3, LR Hitchhiker ID 4, LR Hitchhiker ID 5, LR ID 6, LR ID 8, LR ID 9, LR ID 10, LR ID 11, LR ID 12, LR ID 13, LR ID 14, LR ID 15, LR ID 16, LR ID17 LRID 18, LRID 19, LRID 20, LRID 21, LRID 22, LRID 23, LRID 24, LRID 25, LRID 27, LRID 28, LRID 29, LRID 30, LRID 31, LRID 32, LRID 33, LRID 34, LRID 35, LRID 36, LRID 37, LRID 38, & Non-Vert IDs 1, Tubeworm ID, Polychaete Identification, Live Rock 1, LR 2LR 3, LR 4, LR 5, Curing Live Rock, Live Rock Selection, Shipping/Moving, Placement, Lighting, Water Quality, Live Rock Studies in Fiji Collaboration & ChartsCopper UseMarine Landscaping, Marine BiotopeSumps, RefugiumsFaux Rock,

White funk on liverock   1/26/06 I have a 20 gallon high saltwater tank that has about 7 1/2 pounds of Fiji live rock, along with a couple damsels and a Sally lightfoot crab. my question is this: our live rock is looking really nice ( was cured before being added to the aquarium) except for one thing. there is a whitish, almost spider webby looking coating on some of the rock, which didn't show up until after we added the fish. the sally lightfoot crab pulled some of it off and it seemed like he ate some of it, but there's still some on there. what is this stuff? and how do i get rid of it? i would have included a photo but my digital camera is all messed up. my boyfriend and i are new to the marine aquarium hobby, and want to do everything we can to get this small tank going well so we can upgrade to a larger aquarium. we like your site a lot, and ya'll really seem to know your stuff. i wasn't able to find anything on the site about the stuff on my rock. once we get this aquarium going well, we would like to upgrade to at least a 90 to set up a mini reef, and eventually (once we have a house with more space) have a shark tank. i was interested in the banded cat sharks, since they stay smaller. we've read your FAQ section on sharks, and done a lot of research, and we've come to realize its going to be a while before we can afford a large enough tank for such a fantastic animal to be happy. thanks for the help ~Erica and Eric <Is just decomposition products... likely not harmful... will be replaced, succeeded in time with adequate light, circulation, water changes, time going by. BTW there is no such word as a lot, i's are capitalized, there are spaces between sentences. Fix this all before sending. Bob Fenner>  

Live Rock ID questions....  - 01/24/06 Hi, Being new to using live rock, I've spent countless hours in the last few weeks reading through your site. All I can is thanks...I have yet to find another resource that's been as helpful and informative as yours. I've attached 2 pics of some growth on my live rock that I haven't been able to identify (though for all I know they are extremely common), and I was hoping you might be able to help me. <Only the second one came through> Picture 1a - There are two red circled items - one is branch-like and one is a collection of clearish/green round balls. The yellow circle is of some small green sprout (these type of sprouts have been popping up all over the place). <Very likely a pest algae (Valoniaceae). See WWM re Greens> Picture 2a - I've had a lot of small green sprouts that look different than in picture 1, they seem to look more like blades of grass, and are starting to cover the entire rock. <More algae...> I appreciate your help...I'm not entirely sure what I'm looking at and with all I've read about nuisance growth on live rock, I'm worried that I may be seeing a future problem in the making. <Not a problem... will cycle out mostly... can be controlled biologically, through careful maintenance> If it matters, this is Caribbean live rock, supposedly from Haiti. Thanks again for all of your help, and your great site... <Welcome and thank you. Bob Fenner>

Unidentified creature - 19/1/06 Hello, I have a question about a creature that we have found on some live rock in our aquarium.  We have a 65 gallon tank and got a new piece of live rock.  On the rock there is a creature that looks similar to a barnacle.  He sends out a kind of web of fine fibers, lets them swirl around in the water flow for a while.  Then he, bit by bit, draws the fibers back into him.  I also saw him sort of spitting out these small orange pellets about the size of the tip of a pen.  I was wondering if you might have any idea as to what this creature is.  His web is catching on some of my soft corals and attempting to pull them toward him.  Of course their a bit stronger than his web and he is unsuccessful.  Any help in identifying him would be appreciated.   <It sounds like it could be a Vermetid snail. Do search WWM, the web for more information on these interesting creatures (A good article can be found here: http://www.reefs.org/library/aquarium_net/0897/0897_8.html. Enjoy the diversity of life you have! Best regards, John.> Thanks, 

Live rock ID Dear Team at WWM, as a proud new owner of a 10 gal tank with live rock (no fish yet and not soon planned) and as a newbie to the saltwater experience I truly enjoyed browsing your website for the last couple of weeks. I learned tons of stuff, thanks! I still couldn't find anything there or anywhere else on the web that would've helped me ID something that came with my rock (please see attached image) <A nice pic... but need close-up/enlargement of item #2> Circle #1 is a tree-like structure about 1" and it is attached to the rock. There is smaller alike looking structure growing in its neighborhood. <This is very likely a hydrozoan... perhaps a Stylasterine> Circle #2 is a .5" long oval shape and it seems to have three spikes sticking out of it. I feels like it is filled with a gel-like substance. <Sorry to state, but my eyesight is so feeble, that even enlarging the pic, losing acuity, I can't make this out. Please send another more resolved image if you can> Thanks a bunch for your help! Bettina
<Oh, neither are harmful, need to be removed. Bob Fenner>
Re: Live rock ID  1/16/06 Dear Bob, You are fabulous! Thanks so much for the super quick response! I could not get a better picture of #2 since this thing is so tiny, but after doing some more research on your site, I think it is some kind of sponge, it "breathes" and what I thought to be spikes turned out to be holes. Thanks again, what a terrific hobby! Kind regards. Bettina
<Thank you for your shared enthusiasm. Bob Fenner>

LR Growth ID - 01/09/2006 WWM, <Hello Bryan.> How's life under the reef? <Actually, wonderful (except these confounded cement shoes!).> If you could, I ask for your endless knowledge in helping me ID this growth I have on one of my rocks. <Hmm...Endless? My sister used to convince me to pay her 25 cents to help me eat my ice cream, so it wouldn't melt!> Let me know if the picture does not come through. <Got it just fine.> To the touch it is hard and semi-rough; nothing like a sponge feeling. It kind of looks like a star polyp colony, but with no polyps, and I pretty sure it is not that since I have successfully reproduced those before and know what they look like. I'm thinking it's some kind of stony coral, but have not got a clue as to what kind. I have been through all my books and have found nothing.  What ever it is I hope it keeps growing; the bright pink color will make an awesome addition to the tank. Any suggestions? <One, for a start anyway. It appears to have pseudopodia extended at the ends. Try a Google search on foraminiferans; specifically Homotrema rubrum. It would be a good sized cluster, but it looks right to me. If you have it, look in Sprung's invertebrates book also.> Thanks guys!! <Gladly. Let us know if this is correct or you need more help.> Bryan
LR Growth ID - 01/13/2006 Josh, <Hi there Bryan!> Thanks for the information. I'm pretty sure now that you were right on the mark. <Glad to be able to help.> I did find various pictures and articles that are almost identical to the one in my tank. My only question now is "what" exactly is it? <That's a good one! These are great filter feeders to have and a nice decorative addition.> Everything I've read just referred to it as Homotrema rubrum or species, and almost always had "seaweed" somewhere in the paragraph. Is Homotrema rubrum a type of hard seaweed? <The seaweed bit was probably in reference to the role that Foraminiferans play in feeding them. They are actually not considered plants or animals, but Protists (yeah, I had to look that up). I found a great link for more info. http://www.reefkeeping.com/issues/2003-07/rs/index.php . Hope that helps you out.> Thanks again
<Quite welcome. - Josh>

White Cobweb With Bugs - 01/01/2006 Hi there - we have a marine tank which has been "previously owned". Set up a month ago with four inherited fishes (a Yellow Tang, blue Damsel and two green damsels). All fishes ecstatically happy. All snails happy. Nitrate and Nitrite levels good, <Meaning?> phosphates under control. <As in?> The only problem seems to be the small piece of "living" rock we inherited. Its full of life, despite its size and treatment to date. <Resilient stuff.> It has just started growing a white gauzy mould which is spreading fairly quickly. <Probably sponge growth.> Underneath the film are tiny little clear ticks - fast moving and confined to that rock. <All throughout your tank most likely.> They're multiplying fast. Can you tell us if we should be worried and what it is? <Nothing to worry about except excess nutrients perhaps (fueling the rapid growth). Otherwise normal developments.> Thanks, Jon.  

Items On Live Rock - 12/29/05 I have these items that look like "white commas" on the live rock. The cleaner shrimp does not seem interested in eating them.  I have two photos (the second being zoomed in).  Any ideas on what these are? <<Yep...a Serpulid worm of some sort...harmless if not beneficial...nothing to be concerned about.  EricR>>

The Mysterious Critters of Live Rock  12/7/05 Hello there! <Hey Jess! Adam J with you this morning'¦well almost noon now.> I looked through a ton of postings and did not find the answer to my question, so here it is. <Okay.> I have noticed what look like eggs in my reef tank. They are white, fuzzy, shaped kind of like a tear drop, and have these almost transparent white things coming out of the bottom of them. I'm guessing this is to pick up the stray bacteria in the tank to provide nourishment for whatever is growing inside of it.  <Stray nutrients would probably be a better term.> They are suspended from one of my live rock "caves" and there are only two. I have a serpent starfish who hangs out by them all the time. Also, a peppermint shrimp, a banded coral shrimp, snails (who are reproducing like crazy), hermit crabs, a yellow tang and a tiny clown. Any ideas what they might be? <Well as you mention below a picture is the best and only way I can even come close to a positive identification though I will take a few guesses at it. The white ball sounds very much like a sponge but the 'feathery appendages' you mention make it sound rather like some type of tube worm (possibly a Spionid/Chaetopterid worm) or even a barnacle, could even be some type of hydroid. I know that's a broad list of very different animals but without any more detail or pictures that's really the best I can do.> I tried to take a picture, but they get blurry when I zoom in close enough to see them. Thanks! <Sorry I could not be of more help.> Jess
<Adam J.>

Liver Rock Hitchhiker/Limpet 10/12/05 Thank you for the pointers Ted.  <<You're welcome.>>  I've checked through the suggested areas and come up with two other 'what is it' e-mails from the WWM archive. The problem now is that one response says that the limpet is fine and will browse on algae, diatoms etc - the other says it may be partial to corals... What would your best suggested course of action be?  <<Observe him/her as well as your corals. It is likely harmless but you never know. If you find yourself worrying, remove him/her.>>  The creature has stayed grazing within a small area since I first spotted it 3 days back, and seems to be eating algae. I've attached a marginally better picture. Any advice much appreciated. While watching this mollusk I also noticed this other strange phenomenon. It appears that something has made a home out of old coral, shells and sand held together with a web like material,( much like a fresh water caddis-fly larvae would). The tube is around 5cm long up a piece of live rock. No animal is visible,( but I suspect a worm), I know it's a awkward ask, but friend or foe? <<I would agree that it is likely a worm. Most are beneficial although some are bad news. At this point, I would simply observe things.>> Thank you again. Bob Mehen <<You're welcome and good luck - Ted>> 

LR Hitchhiker 10/10/05 Hello Again good people of W.W.M., <<Hello Bob - Ted Here>>  Please can I once again ask for your help with an identification problem? While watching my aquarium tonight I noticed a new inhabitant on one of the pieces of live rock. It is about 2cm in diameter, mainly rusty brown in colour , but with a series of paler rings bisected by green/white dots radiating out from its centre. The middle of 'it' is slightly raised. It looks a little like some of the chiton species we get here in the UK, but without the obvious segmentation. It has no visible opening on it so I don't think it's a sponge or ascidian and I haven't found a match in your FAQ's. The live rock is supposedly from Indonesia if that's any help! <<It can be difficult to identify LR hitchhikers with or without a picture but a couple of possibilities come to mind. Please search WWM for Stomatella and limpet and see if your critter looks like these gastropods.>>  Thank you for your help. Bob Mehen, Cornwall, UK. <<You're welcome and cheers - Ted>> 

Live Rock Bio-Diversity 10/7/05 I have a 37 gallon reef tank, live rock soft corals etc..... Anyway, I have these small little colonies of tiny almost microscopic shrimp. They are transparent and they are definitely not copepods.  <Honestly without a picture or more thorough description it's nearly impossible to give you an exact identification. One of the marvels of live-rock is that there is a large variety of life on it, what most aquarists refer to as bio-diversity. It could be a number of things from Mysid or mysis shrimp to amphipods. Please see here: http://www.wetwebmedia.com/ca/volume_2/cav2i3/Live_Rock/live_rock.htm (and use the related FAQ's links above it) .>  So my question is are they going to start eating stuff off my live rock or soft corals?  <You'll have to identify them before we can say if they harmful or not. I wouldn't worry to much most of the live-rock microfauna causes little to no intrusive damage, Adam J.>

ID these creatures please  10/4/05 Hi there, <Jennifer> Just today, when I turned off the lights, I noticed 2 tube-like things coming out of my live rock.  The best way to explain them are like an elephants trunk, they very light brown (almost clear) and stretch out 3 or so inches.  When they come in contact with part of the live rock they look like they stick to it for a second and them move on to another area.  I saw another one on a different piece of live rock that looked longer and almost striped horizontally black.  Each one of these things look like they shrink into themselves when lights come on.  Just wondering what these things might me and if I need to worry about them.   <Likely some type of tubiculous worm... of these, probably some sort of sedentariate polychaete... not harmful> I also have one piece of live rock that have BRIGHT neon green tubes (1/2 inch about 15) all over and nothing has come out of them.    Any ideas? <Please see WWM re Live Rock and Marine Invertebrate IDs. Bob Fenner>  

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