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FAQs about Live Rock Hitchhiker/Creature Identification 6

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 ID 8, 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, & LR Hitchhiker ID 4, LR Hitchhiker ID 5, LR Hitchhiker ID 7, LR ID 9, 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,

Feather Dusters the Common Hitchhiker  9/23/05 Hi Bob, <Actually his younger friend Adam J here with you.>      I started my Saltwater tank a few months ago, and it has been thriving. Due in part of your site - thanks! <I'll pass along your gratitude to him.>     My collection includes a Fox Face, Blue Tang, Maroon Clown, Anemone, Scarlet Shrimp, Emerald crap, and a few snails. Also I have an abundance of live rock. <Well you don't mention tank size so it's hard to comment on your stocking list.>      Recently I noticed under the live rock there are a couple of "things" that look like a radar dish, translucent with white/black lines - basically an inverted cone. I noticed at one point one of them receded under the rock, and then popped up some time later. Whet the heck is this? <This my friend is one of the harmless joys of live rock. It's actually a worm, some call them tubeworms, and others call them fan worms.  Most folks in the hobby label them with the name 'feather duster.' The inverted cone you mention is actually its 'crown.' They use this device to capture particulate food within the water column. The actual worm is more than likely residing in a calcified 'tube' (hence tube worm) behind the crown.> I just recently noticed the second one - I hope that this isn't harmful, but if anything it is quite cool. <Not harmful at all, and very cool. These are filter feeders and the ones that arrive on live-rock are amongst the hardiest.  Very Common, in fact I would be surprised if I didn't see at least a few in a shipment of live rock'¦.see here for more detail http://www.wetwebmedia.com/feather.htm.> Thanks for your assistance! Craig H Brockman <Anytime, Adam J.>
Re: Question - Saltwater Tank, Feather Duster/LR hitchhiker
Thanks Adam - sorry it is a 26 Gallon Tank. <No problem, but 2 of your animals have a potential size of almost 12", so in the near future you may want to think about an upgrade or replacement of these animals.> <Adam J.> CH Brockman

Pods and Algae  9/21/05 Dear Bob, <Bab> Thanks for the help on my dead live rock. The rocks are starting to come back alive and the coralline is starting to show itself. Here's one of my questions, 1) is green coralline alright or should i try to get rid of that, I am also getting orange coralline and don't know whether I should remove it or let the diversity thrive. <Let it> Another question is that I have recycled my tank for a month and a half and my pod population is VAST, running all over the glass, sand and rocks. Besides adding a Mandarin Dragonet which eat pods should I get anything else to keep them in check or are the little critters good for the environment. <They're fine... will come, go...> One last question is that I plan on starting a refugium for my 40 gallon tank since you highly recommend it for an added buffer to the Display, what size should I use, I know bigger is better but in reality space is an issue also. Would a 15 gallon work alright, and do you know any DIY plans to build one. <A good start... and yes... on WWM, ozreef.org, Reef Invertebrates book... likely elsewhere> I can use the pods to seed it and I wanted to start to grow certain Algaes and plants to help with the nitrites and nitrates.  Also Does a refugium have to have chambers for the water/pump or can I just add an overflow and tube into the tank and an under water pump at the top of the tank pushing the water back up the tube. <Better to build baffles... to direct water, make a backed up area for steady depth for gear (e.g. skimmer), keep algae, mud/sand in about where you want them> Also would a white and actinic light be ok for the refugium or should I only use strong whites? <The whites alone> Thanks a bunch, Jason <Do take a look on WWM... I've separated the FAQs for refugiums into design, lighting.... Bob Fenner>

Live Rock Hitchhikers 9/19/05 Hello, I've just set up my first salt tank about 2 months ago; a 20g extra high with a 20g long as a sump. I bought about 10 lbs of LR and arranged it in the tank so most of it is in good light. I had heard that you get lots of strange things in live rock so I've been keeping my eyes peeled and could identify most of it, but there are 2 things I can't find info on. One is a kind of tube worm, its green with about 10 very fine rigid hairs and 3 tentacles which will wave around a bit and clean off the hairs. when I shine a light at an angle the hairs are shine red. The other one seems to be a filter feeder. I noticed 2 reddish lumps close to each other and watched them I could see a larger area underneath deflate when it was startled. The 2 ends are about 1 cm apart and both retract when disturbed. Thanks for your help. <It is impossible to guess what these might be, especially without photos.  However, the vast majority of sessile critters are totally harmless if not beneficial.  Enjoy them!  Best Regards.  AdamC.>

Strange coral? Hi, <Hello there> A few months ago I purchased a very interesting piece of  live rock.  At the time it only had two types of green algae/'seaweed'  (grape Caulerpa & some grassy type) among some tiny anemones, green polyps  & 2 very tiny brittle stars.    In the past few weeks, however, I noticed underneath the suspended rock was   some growth that looks a lot like roots of a plant (only this is very white   in color) sticking thru the holes of a pot, however, it is accompanied  by many hollow translucent tube-like structures (also white) with open  ends sticking straight out (about 1/4" long).   I have not been able to identify this.  The growth seems to be picking  up, especially since I introduced weekly vitamin supplements (Coral-Vite).   This stuff has started to spread to the top of the liverock and has even started   sprouting on my fake coral pieces; now and I am concerned that it may become   intrusive and choke out the valued life in the tank.  But if this is  something interesting, unique or desirable, I would like to know. Do you think you could ID this, or would you need to see a photo? Thank you so much in advance! Best regards, Gina Dubel <Impossible to tell what this is from the description... Yes to the photo being valuable. Not likely a coral though... from the description, quick growth. More likely an algae... Many such ID's on WWM... See here: http://www.wetwebmedia.com/maralgid.htm and the linked files above. Bob Fenner>

What is this??  9/13/05 Hi WWM, Found this critter in a tank that had been set up since Feb.  The live rock came from a three year old established tank, however the sand was new.  I did not add this critter, and find it hard to believe he was a hitchhiker on  the rock that came from the other tank as I have fish that would otherwise eat things like this (trigger, harlequin tusk, bamboo shark).  Is it possible he came from the live sand?   <Not likely... is a chiton... a polyplacophoran... lives on hard substrates> It looks like some kind of sea cucumber to me, and I have read the cautions and warnings about these guys, any suggestions??  I don't want/ need any wipeouts!! Thank You for your help!!  Jen Marshall <No worries. Bob Fenner>

That's Why They Call it Live Rock! 09/09/05 Thanks for your advice.. should I just keep an eye on the fish to make sure it's not a baddie? Or is there some action I should be taking?<<Yes, about all you can do>> Also..... (I must stop rock staring,... I've spotted something else) Its about 1.5cm long.. looks like a pale grey slug but has an oval crust/shell looking thing on the half nearest the feelers/eyes. On this, it seems to have its own legs or feelers/whiskers. This part is darker grey with a white strip on the left hand perimeter. When the light was off it stretched upwards on its base. Could it be a snail that has lost it's shell to a hermit crab or is it a sea slug of some kind? Are there any bad things I should be on the look out for to come out of the LR? <<The pods, snails and other infauna that lives on the rock is actually quite interesting. It sounds like you have found a Stomatella snail. There are some hitchhikers that can be a problem. Crabs for example. Please search WWM for "Stomatella", "marine snails" and "crab compatibility".>> As for the damsels.... the Gramma has been irritated by them but they don't seem to be causing too much disruption. The tang chases them off a bit too. What extent do you mean I should quarantine? I float them in the bag for 20 min.s and introduce some of my water but I don't have a spare tank to put them in. Is that what you mean?<<No. Please read the material in this link: http://www.wetwebmedia.com/quaranti.htm and search WWM for "marine quarantine procedures">> Thanks again... I'm certainly learning as I go along...Think I may give up though if I find a 2 foot long worm, like one of your readers did in his 4 foot tank. That would give me nightmares. Rebecca <<You're welcome, good luck - Ted>>

And Life Sprang From The Rock! - 08/25/05 Thank you again for the help with my sponge question, but now I have a new plague attacking my tank. <<Hmm...ok...>> To recap I have a 12 gallon salt water tank reef tank. <<I recall, yes.>> The problem is that on my live rock I have found hundreds of extremely small white, thin organisms.  These look almost like tiny hairs all over the live rock.  They resemble bristle worms, just stationary and extremely small.  I even have a few growing on the casing of a feather duster.  Are these dangerous?, will they get big?  And foremost, how do I get rid of them if they are a threat? <<Well Josh, one of the great things about live rock is the preponderance of life that can, given the chance, spring forth.  I can only hazard a guess, but what you are seeing is maybe the tube of a worm, or some form of algae/calcareous algae...likely harmless either way.  If it is a worm, the population will be self limiting and likely to wane soon unless you have an excess of available food/detritus in the tank.  Keep an eye on things (and enjoy the wonderment) as you have, but I don't really see anything to worry about here.>> Thank you again, Josh <<Always welcome, EricR>> Syconoid Sponges...Probably - 08/18/05 Dear Crew, <<Hiya!>> I have a problem that I hope you can solve. <<I'll give it a try.>> I have a 12 gallon reef tank with almost 40 lbs of live rock <<Yowza!...how do you have room for anything else?>>, 3 inches of live sand, a 10 gallon refugium, 65 watt power compact 50/50 light, 1 blue damsel, a green Chromis, and a hi-fin shrimp goby, a cleaner shrimp, 6 red hermits, 7 snails, and various corals. On one rock that houses 6 red mushroom corals, I see about 20 small, white,  cotton ball looking objects. <<A sponge of sorts most likely.>> The fish seem to stay away from it, as well as the hermits and shrimp. <<Hmm...likely not related to the sponge.>> The cotton balls also have feather looking objects coming from the top.  Some are about half an inch tall, the others are about 1/8th inch. Do you have any idea what these are, or if they are dangerous. <<Sounds like Syconoid sponges...harmless if not beneficial.>> I did have one leather finger coral die and almost dissolve before I figured it was dead (it didn't lose any color.  Could this be spawn of it. <<Not likely in my opinion...would look to other sources/problems.>> Also what confuses me the most is they are on the back of the rock, out of the light, towards the back of the tank. <<Yes...many sponges prosper in these type conditions...helps prevent being overgrown by algae.>> Thank you so much Josh <<Always welcome my friend, EricR>>

Syconoid Sponges...Probably (II) - 08/19/05 Dear Eric, <<Joshua>> Thank you so much for the info.  It really eased my mind. Joshua. <<Is my pleasure to assist and assure.  EricR>>

Invert Questions - 08/04/05 Hello Bob, <<Eric here>> I'm so glad I found your site, it's very informative! I hope it's ok to send you emails. <<Yes, quite>> I have several questions regarding invertebrates, but I'm at the beginning of cycling the tank - I'm a newbie. <<Welcome to the hobby>> 1. I think I have a Christmas tree worm - it's fairly big and has those Christmas tree bristles and lives in this rock.  I like it, but I'm cycling my tank - is it going to die?? <<Possibly...cycling/curing live rock involves a certain amount of die-off.>> I can't feed it b/c I'm cycling - what should I do? <<Leave it be.  You likely can't provide anything not available (or not) in the tank already.  Christmas Tree/Feather Duster worms feed on micro-plankton/algae, bacteria, dissolved organics...most foods attempted by aquarist are too large/unsuitable for these creatures.>> 2. I have this weird grey matter on one particular rock that has this short grass on it, it just started showing up.  I think the grass is dying - is this anything I should concern myself with? <<Nope, all part of the natural progression.>> 3. On this same note with that same rock with grey matter on it - there are a lot of calciferous worms on this rock.  I don't mind them, but I wonder if they are spawning?? <<Or maybe just reappearing after disturbances from transport/handling.>> They seem bigger and I see little calcium tubes growing on other rocks - I think I even see a weird spore!  It's fuzzy, whitish, and has a tiny hole at the tip. <<likely a Syconoid sponge, nothing to worry about.>> Is this particular rock with all this life on it bad for cycling the tank? <<Rock with "life" is desirable...some life forms will disappear...others pop up later...all part of the "cycle.">> I think I'll end up w/a lot of worms. 4. I saw a reddish worm with lots of legs about 1/2" long.  Is this a fireworm and should I remove it?  I'm hoping it's harmless, I wouldn't mind keeping it. <<More likely what you saw was a bristle worm, a beneficial detritivore.  The "legs" are actually sharp, fragile "bristles" that can be painful to the touch...best not to handle with bare hands.>> Thank you for your time, I look forward to hearing from you when you get the chance! Steph <<My pleasure, Regards,  

What the heck is this? 7/28/05 I found this on my live rock. It is about half an inch high and seems    to grow fairly quickly. It is low in the tank and has a jelly -like    consistency. I have also seen what looks like the beginnings of a    second one of these beginning to grow on another rock. My 75 gallon tank is 2 months old. Hope you have an idea about this    as I have searched for over a week on this one and have not even come    close to an id. The fact that I may see a second one is somewhat    concerning. Let me know if you think this thing should stay or    go. Thanks, Anna <I suspect this/these is/are the beginnings of sponge colonies... the one pictured being overgrown by some sort of filamentous red or blue-green algae... not to worry. I would not remove, destroy. Bob Fenner>

Hitchhiking White Specks 7/27/05 I've noticed in the past 3 - 4 days, since the introduction of my last Fiji live rock, I've started seeing small white specs that look like the beads out of a medicine capsule. I've found no pictures or descriptions. Can you give me some kind of idea what they might be?? The Fiji rock even came with a hitch hiking brittle star.. <Yes, live rock is often covered with life. This is a hard one, provided that, without photographs or an extremely detailed description, an identification is near impossible. I thought about this one for a long while and came up with the possibility they might be micro-jellyfish. sadly, they are not indigenous to Fiji, so I have nothing. Copepods, perhaps? In any case, I doubt you'll ever get a solid answer without a photograph or much, much more detailed description, but I can tell you this: I doubt they will do any harm to future life forms destined to inhabit your aquarium. In fact, I'll bet they disappear soon enough. Good luck with your new tank! Mike G> Steven J. - Live Rock Stowaways - Hi, I've spent many hours looking through your web site and found it fascinating and extremely helpful. I do, however, have a question that I'm struggling to find an answer to. I've been an aquarist for many years but only temperate and tropical freshwater. I've recently set up a 30 Gallon tropical marine tank, SG = 1.022, temp = 25C, pH 8.3. Nitrates are below 15ppm. 2 x Fluval 104 MSF External filters with a power head in the tank for extra circulation. 1 x Daylight Plus fluorescent tube (30watt) + 1 x Blue Moon Actinic fluorescent tube (30 watt) It's been up and running for 2 weeks now and last week I started adding some live rock into the tank. (I can't afford to buy it all in one go so I'm building it up gradually) <Understood.> I'm not adding any fish or inverts until the tank is fully cycled and the filters have a compliment of nitrifying bacteria. <Good plan.> My main concern is that I've noticed various life forms living in and on the live rock that I've put in (shock horror! it is live rock after all but I wasn't expecting this kind of life on it!). One of the pieces has some polyps which appear to be Parazoanthus axinellae growing on it and another rock definitely has a small crab living in it as well as some kind of shell fish and many tiny lice type things with long pale white "whiskers". As the tank has not fully cycled yet I am worried that all these things will die when the ammonia peaks while the bacteria colonize the filter media. <Well... it does sound like this is very live rock and I wouldn't be too concerned. When you purchase cured rock from a fish store, you often dash through the cycling process exactly because of the tiny animals you're seeing. Keep you eyes on the nitrogen cycle and likely all will be fine.> There's only a few pounds of live rock in there so I don't think they would be sufficient, or would they? <Every little bit helps.> Please help if you can. <No help needed, you're doing just fine. Do try and add some more rock before you start with the fish.> Best regards and keep up the great work you guys are doing, Leif Birmingham, UK. <Cheers,  

- Live Rock Hitchhiker ID - Well, I have waited for a few days for a response and have not received one yet, so I am wondering if this went through the first time, or if the fact that the photos that were embedded became so grainy after sending (for some reason, Outlook 2003 screws up embedded photos) to the point that you can't do anything with them, or if you guys are simply so busy that you haven't had time to respond to my request for ID yet. <Well... we're all private individuals with our own private Idaho's, so sometimes we're just not as timely as we'd like to be. My apologies.> Regardless, I am re-sending with the photos attached in the hopes that these will come through properly. If you need anything else from me before you can figure out what is going on, please let me know. If you guys are busy and just haven't had time to respond due to trying to catch up after the Memorial Day weekend, then please accept my apologies for re-sending. <No worries - will respond to your email below.> Thanks, Shane The original email follows: This is my first attempt at reef-keeping and I started out with a 2-gallon Nano Reef.  Not the easiest way to go, I know, but I find them fascinating and finances dictated that I start out small and move up. <You will find in the long run that just because the tank is small that your capital outlay will not be similarly small.> Anyway, I purchased some live rock and this little critter was attached to it. I have no idea as to what it might be.  Can you assist with identification, please? <I will do my best.> My apologies for the quality of the photos. <They are more than good enough.> I had to hold the camera by hand due to the angle of the shots that were taken to get the best possible view of the specimen. This is what it looks like closed up. And, a couple of shots when it opens up (see attachments) I would like help with this as I am so lame, I can't tell you if this is an anemone or a coral. <Hard to know for certain... looks like a polyp of some sort, but then again could also be a Majano anemone, which would be undesirable.> Heck, I was even thinking for awhile that it might be a sponge, until I finally saw it opened up (it has been in the tank for about two weeks and today was the first time that I saw it opened up, although my wife says that she has seen it opened up before). The last shot I took with a flash and there was no reaction to the flash by this specimen (something that I don't normally do, but so far I only have a few hermit crabs, some sponges, an Acropora and a Montipora Cap coral. I didn't think that they would be affected by the flash and this critter didn't seem likely to be affected by a flash either. In hind sight, it may have been a dumb move and I won't be doing that again). Any help or ideas would be greatly appreciated! <Would suggest you read Steve Pro's article: http://www.wetwebmedia.com/ca/cav1i3/aiptasia_impressions/aiptaisia_impressions.htm There's a picture there of a majano anemone... these often go through stages of being more or less inflated. If you see the tips begin to swell and become more tubular then this "critter" is majano and you'll want to take steps to eliminate it. If not, then I propose you enjoy it as it will likely cause no problems.> Shane
<Cheers, J -- >

Live rock creature... using WWM 7/21/05 Hopefully you can help me identify some creatures i have in some live rock  i got over the weekend.  I couldn't get a picture cause they are just too   small to show up.  They appear to possibly be some kind of shrimp I'm  guessing.   They are no more the 1/4" long and they have antenna and a dark  brown body.   The body is straight and curls under some at the end.   They are very quick moving critters.  I'm just hoping they are not baby  mantis shrimp.  Please let me know what you think they could be.   Thanks. <... please read, starting here: http://www.wetwebmedia.com/invertidfaqs.htm and on through the linked (blue) files... Bob Fenner> Odd red branch ID 7/13/05 I got a shipment of live rock from FFE the other day to top off my system (29 gal 2 years old with 2 false Percs ,LTA, Candy cane coral and numerous mushrooms. Anyway I was lookin at a piece the other day and I noticed a skinny bush looking thing. it had a base that forked up and kept on forking. It is red and has numerous spines coming out everywhere. I would send a pic but my camera is down:(  Can you help me ID this thing? Thanks for your time -Aaron <Sure. Start reading here: http://www.wetwebmedia.com/marinvind1.htm Bob Fenner>

Live rock ID 7/7/05 Hi there,  I have just bought some live rock for the first time and can not find on your website what the round thing is.  Can you help?  It is smooth, round and dark greyish. thanks Dawn <Is it hard to the touch? Looks like a colony of some sort of stony coral... perhaps a Poritid. Soft? Likely a sponge of some sort. Bob Fenner>

Marine Tank unknown... serpulids 6/29/05 Hello, My name is Kevin.  I have had a marine tank for approximately 3 years with no major problems.  Recently I have noticed white spots on my rock as well as on my tank.  Nothing on my fish as of yet.  The white spots seem to curl around like a snail shell would do.  I am not sure if they are possibly baby snails since I can not find any pictures.  Can you tell from the description or would it be easier to tell with a photo.   Thank you for your time. Kevin <Are very likely tubiculous sedentariate polychaete worms... Please see here: http://www.wetwebmedia.com/polychaetes.htm at the bottom... read the linked files above. Bob Fenner>

Hitchhiker ID? I have a hitchhiker on my live rock.. (the first of many to show up), I hope.  Its so small, I'm not sure I could get a good photo. Its a small bright red round dot (about 1/16" to 3/32" in diameter) when fully open. It almost has a crater type look, but not real deep.  When shining a flashlight directly at it, it stays open, but when removing the light, it closes up instantly about 75% and then slow reopens over the course of the next few minutes.  Any idea what it might be? <Mmm, not much... perhaps a small polyp animal of some sort... Maybe a magnifying glass, or taking a high resolution pic with a close up lens and "blowing it up" would help here. Bob Fenner>  

Species ID Hello WWM crew, <Don and Nan> I am new to the hobby and I am having difficulty identifying something growing in my aquarium.  Please see attached photo.  I have these small pinkish blobs growing in a lot of places on the live rock.  Some are growing clear tentacles as shown in the photo.  What are these?  Are they problematic (i.e.. pest)?  They are not growing particularly fast, but they are certainly multiplying.  If it is a problem, how do I deal with it or get rid of it? Thanks for the help... Don Ouimette <Some type of sponge/poriferan... See WWM re... not harmful... Bob Fenner>

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