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FAQs about Live Rock Hitchhiker/Creature Identification 4

Related Articles: Live Rock, Answering Some LR FAQs by James Fatherree, Live RockReef Systems, Refugiums

Related FAQs: LR Hitchhiker ID 1, LR Hitchhiker ID 2, LR Hitchhiker ID 3, LR Hitchhiker ID 5, LR ID 6, LR Hitchhiker ID 7, 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, Refugiums Faux Rock,

Live Rock Question 4/17/05 Hello, Great site!!! I've been sending any aquarist to this site just for the education.  <Thanks!... for the kind words and referrals!> Anyway, I just purchased and cured one piece of live rock. I've added it to my display tank. What I'm wondering is what types of algae should I expect to see growing on it? I've been having red algae on some of my gravel and on a piece of dead rock (don't know the name of the rock, but it looks like a brain and has tiny little holes in it). It's like a blanket and I have to scrape a little to get it off when I do water changes. I change 10% of the water every week and vacuum the rocks during that time. I'm debating on doing 5% twice a week instead to reduce the algae production. This red algae is beginning on my LR, but is this a problem?  <The red algae you described is actually Cyanobacteria. Siphoning it helps, but ultimately it must be controlled through a combination of three factors: Reduced nutrients, high alkalinity and strong water movement.> I've got a 46 gallon bowfront FO, (I guess its now FOWLR since I've added a rock), under gravel filter powered by zoomed oscillating power head. I've got an external filter with carbon in it and an AquaC Remora Skimmer. I keep me feedings to a minimum. My water temp is 81 degrees, ph of 8.1, Ammonia, Nitrites, and Nitrates are at 0. Any help would be great. Thanks!!! Jim V.  <The undergravel filter may be part of the problem. They are notorious for fowling with wastes. A zero reading of nitrates could mean that few are being produced or that something (like Cyanobacteria) is using it as fast as it is produced. Your water change schedule is fine. I would suggest measuring phosphate and alkalinity. Phosphate should be undetectable and alkalinity should be 2.5-4.0 mEq/L. Adding some additional water movement might help as well. Best regards. AdamC.>

Hitchhiker on our live rock Hello, I have recently purchased some live rock to put into my tank. We have this critter that hides under our rock. It only comes out to eat and uses its tentacles to reach for the food and then puts it into its mouth. It's body size is about the size of a 50 cent piece. The 5 tentacles average about 4 inches in length. Its eyes seem to be between two of the legs and its mouth is on the underside of the round body.  Please help us identify this critter. We will be starting to get some coral soon and I want to make sure that it will be ok with the hitcher. <Melissa, it certainly sounds like you have a brittle star under that rock. Shouldn't cause any problems with anything although they have been known to capture and eat very small fish. James (Salty Dog)> Thanks a Million,  Melissa Gill 

All the Way to Alaska - Hitchhiker Good Evening from Alaska, <cheers, mate> I got me a great live rock the other day. I was attracted to it because it had an empty bi-valve shell open on (very pretty), had two attached closed shells on it and it was covered with coralline algae. So, about a week later, after my Frogspawn kept getting knocked over, I went to perch it back against the shell rock and noticed that the shells moved, and the reason my Frogspawn kept falling. Based on my own previous experience of harvesting oysters and clams in Hood Canal, WA, it seems to me these are oysters. The closest I can find on your site is this: Spondylus violacescens. Apparently the rock came from Fiji. <interesting> So, I feed with DT's about 3 times per week, and with frozen Invert Food about 2 times per week. Since I noticed the little critters, I have been target feeding them also when I feed the rest of my corals. <you were (or at least may have been) lucky to get no worse hitchhikers for lack of QT for this rock. Yikes! Please heed this strictly my friend... QT all new livestock, rock, fishes, corals, etc. (anything wet!) faithfully for 4+ weeks to prevent the risk of introducing disease, parasites, predators, etc> 46 gal, established tank. The largest fish in here is Briny, the Bi-color Blenny. Frogspawn is my most "elegant" coral, with mostly mushrooms, green star polyps and some clove polyps. Is my current feeding going to accommodate these critters, or should I target feed daily? <hard to say... I'd feel better with live cultures of rotifers and/or phyto. But DTs is a fine product. Consider a refugium too> Do I need to consider mashing up some seafood for it? <not likely... particle size will still be too large. Such filter-feeders favor nanoplankton> Thanks so much (again). Sher H. <kindly, Anthony> 

Yellow and Orange Patches on Rock Howdy. What can you tell me anything about my aquarium from the attached picture, other than it is not exactly over-stocked? <A nice pic of an apparently well maintained system> Are the yellow and orange patches down the middle of the frame an indication that something is wrong? <Mmm, no. Quite the contrary. These are sponge growths/colonies, indicative of good conditions> I have some very nice coralline algae growth everywhere other than on those surfaces fully exposed to the 175W halides 6" from the surface (10,000K screw base Hamilton/Ushio, 160-gal, 24" deep). I've got 8 small to medium SPS so far and all are doing well close to the surface. Also, there is a dark red mat that is forming just under the shallow sand bed surface in the vicinity of some Halimeda but it does not appear to be associated with their root system. Suppose it is bacteria or algae but don't know. I vacuumed some of it up, but not all. Based on that description, can you tell me what it is and if I should do anything about it? <Mmm, leave as is, enjoy> I've got lots of small bristle stars and amphipods along with the normal compliment of snails and hermit crabs, but nothing that you would really call sand stirrers. Cheers & Happy New Year, George.
<To you and yours as well George. Bob Fenner>

Liverock Critter ID Howdy...great resource you offer for all levels!  Thank you!!!   <You're welcome> I've been all around your site and as any individual is rarely like any other, have been unable to find an image that closely represents a critter that has hitched a ride in on a small piece of live rock I just brought home (was marked as Tonga if that helps)...I've attached a not so great image of it (from probably one of the first digital cameras ever made...time to upgrade, I guess), in the hopes that you might be able to identify it for me.  I'm really, Really, REALLY hoping you aren't going to tell me it's Aiptasia, but I fear it may be just that (though it is pretty cool and takes hand-fed pieces of shrimp quite readily...)  It's base is quite transparent and somewhat wide and stubby with long, thin, white, stringy features (for lack of better word...organs maybe?), and it's tentacles are light brownish, but not all that long (as appear on a lot of the Aiptasia pics seem to show, which gives me some hope...) <Err, does look like that notorious Glass Anemone genus...> Any help you might be able to provide would be great...and thanks again for such a great resource.  Your site has been a great help in this new venture....(or, better, ad-venture...!)   Kim
<Hee heeeee! Glad to share. Bob Fenner>

Live Rock Hitchhikers 12/16/04 Hello, just started looking at my new live rock tonight with a flashlight and found a bunch of stuff. <Isn't this a blast?!?!?  One of my favorite reefkeeping activities!> I enclosed a pictured of the first couple I've found, all the others are identified. # 1 I have no clue what it is, looks like a urchin but has wavy tentacles... but I'm sure its not a tube anemone. Doesn't move around much, has a gray bottom that isn't anchored  <I would guess small urchin.> #2 looks like a caterpillar, black and grey with sharp black spines, does  move around <More likely some kind of bristle worm.  Do keep an eye on it.  Most are harmless, but some from the Caribbean are predatory.> #3 I think Is a nudibranch, this tank is destined to become a reef with soft corals ... so should I be moving it to my other FO? <No clue here.  ID's are difficult even with a good photo, let alone a hand drawing (not to knock your artistic skills!).  In general, I try to take an "innocent until proven guilty" approach to unknown hitchhikers.  Truly dangerous/harmful critters are rare and the ones that are more common are pretty well reported in good books.  Best Regards!  AdamC.>  

Live rock critters Hello, I just purchased 70 pounds of beautiful live Fiji rock. I placed it in my un cycled aquarium to help it cycle. One rock is covered in green polyps with orange centers, a vast number of them have turned white but there is a few that have opened up. Will there be some die off then will they grow back? Also I have what looks like some sort of anemone. Its about 2 inches wide, white with neon green tips, do you have any idea what kind this could be? I will have a digital camera within the week so I'll sends some pictures. I have a few oysters or clams on the rock to what do I feed them? They open and close and spit of stuff so I know there alive. thanks a lot. <Hi. I think what you are talking about are zoanthids.  They will be present on live rock and there will be a die off.  If your water quality is good and there is enough lighting and nutrients in the tank the coral will come back.  The oysters or clams are filter feeders and will feed off of the phytoplankton in the tank.  You might have to supplement their diet.  But you won't know that until later on.  Good Luck. MikeB.>

Digitate hydroids I have recently set up my first salt tank and purchased some live  rock.  I noticed that there was some strange come out of the live  rock.  I did an internet search and have found out I have at least two  Digitate Hydroids.  One completely disappears when the light comes on the  other is about a tenth of an inch long.  It is about three inches long with  the lights out the other is about an inch or two.  I have not been able to  find much information on these creatures.  I want to know if they are  safe. << Yes, I would keep them and not worry about them. >> I also need to get a moon light to see what I am missing. << A flashlight in the middle of the night comes in handy as well. >> Thanks, Ed <<  Blundell  >>

LR critters Hi WWM crew. I love this site. I was curing 45 pounds of Fiji live rock that I had ordered from Live Aquaria. I read that if I made the salt level 1.035 and let the rock sit in for a minute worms and shrimp and other critters would flee the rock. About ten seconds after I put the second piece in I noticed this dark worm like creature emerging from a hole in the rocks. It had the earthworm look to it but it was sort of blackish looking. on the tip it had like a cone shaped tip (maybe claws). after about 30 seconds it started to go back into the hole as I came back with pliers ready pull it out. I tried to stick the pliers in the hole it came from and the outside of the hole was soft like a die off from a sponge. What do you think this could be? this thing is still in the rock now and I'm curing it. thanks Joe >>>Hello Joe, It's some type of harmless annelid or feather duster I would guess, nothing to worry about. Having said that, I can't imagine why you want all these beneficial and desirable critters out of your rock?????? Sounds to be like you were given some bad advice somewhere. Jim<<<

New Aquarium recently set up a 55 gal aquarium( about 2 weeks ago) and am currently cycling the it with 10 lbs of LR, 40 pounds of LS (with 30 lbs dead sand), and three damsels. I also have some decorative dead corals in there too. I am running a protein skimmer and two 50 gal. AquaClear filters. A few days ago I started to notice a grayish blackish bacteria ( maybe?) growth on one of the pieces of live rock. Over the past few days brown spots have been appearing on the white coral pieces and the black hair like growth has spread to them and the sand bottom. I have read my butt off, but no mention of this. I was wondering your thoughts. Thanks for any help in the matter. >>>Greetings, No worries. There are all kinds of things, sponges, macroalgae, etc that are going to die off and rot. Just part of the process. You will also get diatom and algae blooms, again just part of the cycling process. Good luck

Growth on live rock Hi again- <Hello> Hope you can help with this one.  My tank is about a year old, FOWLR and a couple of pieces of hardy type coral, chemistry good, all pretty much zero except nitrates running about 10 or so, regular water changes weekly (10%).  I've just gone through a battle with diatom algae and green film.  It took about a month but has cleared up mainly by use of DI make up water supplemented by some GARF grunge and some extra snails. Today I noticed some white cone shaped growths on one of the rocks in the tank.  They are small. about 1/4 inch at the base and about 1/4 inch high.  I've attached a few photos to see if you can make some thing of them.  Any ideas as to what they are?  Should I remove them?  Perhaps snail egg sacks or something? <May be this... or even ascidians, sponges... no need to remove> As always, appreciate your help.  It is a great thing to have you folks here to rely on. Thanks again-- Larry.
<Thank you for your kind words, sharing. Bob Fenner>

White clouds coming from live rock Hi Was hoping you could help me out with a couple of small questions! I have the following specs: - a 55gallon tank with sump. - about 25 pounds of live rock. - 1 Clown Fish - 1 Smallish Anemone - skimmer I intend on adding more stock in due course. I have noticed on occasions, that a cloud of debris puffs out of my live rock.  Do you know what this could be the result of? << Sometimes I see worms and snails doing this, but I'm surprised that you don't see the actual animal.  Strange. >> Is it the result of some creature in the live rock or could this be due to a build up of oxygen from my airstone (albeit the airstone is not near the rock that spurts the debris). << I was thinking some animal for sure.  I guess I'd have to see it happen. >> Incidentally - my friend has also noticed the same thing come out of his live rock. << Could it be a snail (or the like) releasing gametes?  That is probably the most common thing I see like this. >> Do I need more live rock or do you think around 25pounds is sufficient ? Is there a trade off between the amount of live rock and the amount of space for my fish to swim? << You can't have too much live rock. >> If so when does the trade off kick in? For example is there any validity in saying that a 55gallon tank would become a 30 gallon tank if it is stocked with live rock displacing 25 gallons of water? Or does the filtration benefits of having the live rock in the tank outweigh any of this. << The filtration of live rock is so important that it outweighs all other concerns in my opinion.  Second is lighting. >> Your help is much appreciated. Regards Simon <<  Blundell  >>

Red coralline VS Cyanobacteria Hi guys, hope you are all well. <Hi and thank you we are all well and happy.> I am in the process of upgrading my tank after a near total loss, so I let the tank sit with minimal maintenance for several weeks (which did good- the corals I have left all have come out in full). <Sometimes less is more.>  I have had red-slime problems in the past, and I would siphon it out and blow it off the rocks with a turkey baster.<That is a good practice but I would use the baster first then siphon it out.>  I cannot blow this red stuff off the rocks, its hard to  brush off with a toothbrush (even with toothpaste-:)) it "feathers"  off the rock (like tree fungi), and is nearly the same color as Cyano.  Is  it red coralline? <It is absolutely coralline algae.  If you want to be sure take it out and put it into some vinegar.  If it bubbles then your are in business.> Thanks for being there to answer oddball questions! <Not a problem! MikeB> James

Pearl like things? I have these tiny blackish, bluish round pearl like things on some my live rock and hard corals, << Well it looks like bubble algae.  Hard to say for sure, but I'm thinking Derbesia osterhoutii or Valonia macrophysa.  Either way it is good. >> the more I look the more I find...attached is a few photos.  Thanks for your help. Photos are attached as well... 225 gallon salt live rock,1 cleaner shrimp, 1 anemone, 1 emerald crab, snails, 2 starfish, purple tang, yellow tang, Naso, purple dwarf angel, 2 percula clowns, 4 striped damsels...PH and all levels check out fine.  I use a RO-DI water... Lou Montanaro
<<  Blundell  >>

Questions pest and skimmer Dear WWM:  You are great source, thank you for your work and information. It is really helpful especially for we guys who are in lean country (lean for aquarium market and knowledge).<Glad to be of service!> I am from China, running saltwater tank. I had read lot of your great articles. But still have some questions can not find info. in the net.<I will do my best to help you out.> 1. Can you give an answer/description, or recommend some place/internet about marine aquarium pest? So I (and others friends) can know what normal pests we will meet when we buy coral, live rock, live sand, and fish. Now I know mantis shrimp, and maybe bristle worm and flat worm and fire worm, but only know some of the first better, the others not too much.  <Serious pests are rare.  Most bristle worms are beneficial scavengers.  Flat worms are in most if not all aquariums and only become a problem under certain circumstances.  True Fire worms are mostly from the Caribbean, so they shouldn't be a problem.> 2. Can you give a overview for the noise aspect of skimmers? What is the quietest skimmer in the market now?  <As a general rule, larger skimmers are louder, but a lot depends on the pump.  If you choose a skimmer that requires you to choose the pump, focus on choosing a quite pump.> A good example is which one (Turbo floater or Aqua C EV series) is more quiet under the condition that same skimming capacity is provided.  thank you and regards. Yutong, 041111 <Every model of Aqua C EV will outperform the turbo Flotor, so this isn't a good comparison.  An Aqua-C will only be as loud as the pump.  Best Regards.  AdamC.>

Live Rock Die-off On another note, I purchased a live rock this past weekend and noticed a brown smudge on the bottom, It looks as if the rock has been dipped in chocolate fudge covering many of the growth. In addition, a yellow slime looking, felt stiff, on the to portion of the rock. I don't have a pic right now but can get you one later this week. I was wondering base on your experience on the brown smudge what that could be. I have cruised the net looking for pics but unable to find one. Thanks for any guess. Jorgen Quiban >>>You are almost certainly, in both cases seeing dead sponges - a common thing on live rock. Scraping them off as much as possible will reduce nitrate and algae spikes in your tank. Cheers Jim<<< Whose been eating a Big Mac over my reef tank? Yummy! 11/5/04 Hey WWM, I think Anthony may be the best person to ask this question to. I have a lot of white spots on my live rock. The best way I can describe it is they look like the seeds on Italian bread? While most of the rock has green algae on it. These white spots do not? Is it some sort of a flat worm and if so what would be the best way to get rid of them? Thanks <Cheers, Jim... I do wish I could help you here... but simply need more info (detailed) is not a pic. If removable, please siphon one off and place on a dark background/paper and send the fullest frame shot that you can. Else... are these motile or sessile. Is sessile, are they attached. Do they respond to light cycles? When did they appear? Are you now a Steelers fan since we got Big Ben and soundly repaid the New England Patriots for knocking us out of Superbowl contention in 2001 by ending they 21 game winning streak. Do you think the Steelers will beat Philly on Sunday. Just the important questions :) Anthony>

Red sponges in my SW aquarium? Hello all...first of all I love your site and have been able to answer most of my questions here.  My question is that about 2 weeks ago we purchased some LR at our LFS.  We have gotten rock from them before and while we're not having any problems with the rock per se but I have noticed that we have these growing masses of dark red, vase like sponges I'm assuming, what type are they?  We also have noticed some white gauze like stuff growing on some of the LR and I think we may some orange or red boring sponges.  Are the boring sponges harmful?  Should I remove them, and are the others harmful?  We have no corals only 1 damsel, yellow tang and a camel shrimp in the tank. Thanks, BLK >>Without pictures it would be difficult to ID the sponges, but they are not harmful and most people want them in their tanks! >>Rich

Small worm in live rock Dear Bob, << Blundell today. >> I decided to install my new moonlight last night and discovered a worm like creature coming from my live rock. << You should have many. >>  It stretches out from a small whole in the rock and comes out and sifts the sand for food I guess.  I know it's not a bristle worm, it is striped. << I'll guess it is a peanut worm.  They are beneficial and you will eventually have hundreds of them in your aquarium. >> Please advise me if this would be a good or bad worm. Thank you, Tim <<  Blundell  >>

Assorted Live Rock Critter ID's 10/2/04 Crew: I hope that I am not taking too much of your time, but if you had the chance, I am curious to know what some of these critters are.  I can't seem to find any other information in the Live Rock Hitchhiker ID FAQs, or anywhere else either. Any help you could give me would be appreciated. <please do consider our book "Reef Invertebrates". It is been commented that one of the neatest things about it is the address in text and photos of many of the interesting and uncommonly described creatures found in/with living substrates> id_01_please.jpg - I have several of these little things around, but cannot figure out what they are.  They don't do anything, and nothing really pays any attention to them, I am just curious. <the picture is rather out of focus, but the organism appears to be a demosponge... else perhaps a similar looking colonial tunicate. Harmless filter feeders either way> id_04_please.jpg -  If you zoom into the blue-circled area, at about 200-300%, you will see a worm (I think) that has a multicolor banded tube.  It had been active at night, but the last week or so has begun to come out during the day more.  It seems to stretch itself out to grab food, then contract back outside in to eat, when it is fully stretched out, there is a ring of hairs (cilia) on the tip (for grabbing food probably).  I can't find any pictures like it to help figure out what it is, any help would be appreciated.   <actually... it is a sea cucumber. This one lives inside of hard substrates though.  A phyllophorid. Pictured and described on the first page of the Holothuroid chapter of the above mentioned book> id_07_please.jpg - It is a small (2-3 mm) snail with shell that looks like a more elongated Astrea shell.  I only had one before, but have since found a total of 4.  Their shells are consistently white, with many small, black spots on them, and I can't find any pictures of descriptions to identify it.  It doesn't look like it is doing anything destructive, but I am looking ahead to corals and clams, and trying to identify possible problems beforehand.  I have gotten a closer look, and the body has the same color pattern, white with small black spots, and there are two antennas, but I could not get a good look at its mouth. <hmmm... the pic sequence is out of order here, but I believe you are referring to the gastropod that looks like Cerithium (a cerith). Again... the picture is blurred/out of focus... best we can do here> id_08_please.jpg - Looks kind of like a hardened pile of slime.  It is about 2" by 3" and is pink colored with some orangish-pink striping.  There is also a couple areas that have the same shape, but are brown colored with splits in them (like the cracks in mud once the sun bakes it).  The strange thing is that the splits change in width, sometimes hardly noticeable and other times almost a mm across, it has me stumped. <this image, alas, is completely out of focus. I cannot make out any recognizable form here. A suggestion... I suspect that you are using the digital zoom on your camera at full extension to get these shots? If so... don't :) As an artifact of the software, it completely ruins close ups of aquatics images... it really is just for long distance (landscape) shots at best. Avoid using digital zoom whenever possible. Instead... get your camera lens and subject as close to the glass as possible>     One more question (Last one, I promise).  How big should I allow the bristleworms to get before getting worried?   <they are limited by food/nutrients... if they are growing very large in number or body size, its a sign of overfeeding, inadequate water flow, weak skimming, etc. No worries... just control them by controlling nutrients (export)> I have at least three over 3 1/2 inches, and many more smaller ones.  I am not worried about the smaller ones, just the few "giants." Thank you for your time. Jeremy <best of luck, Anthony>
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