Please visit our Sponsors

FAQs about  Brittlestar Reproduction, Regeneration

Related Articles: Brittlestars, Sea Stars

Related FAQs: Brittlestars 1, Brittlestars 2, Brittlestars 3, Green Brittlestars, Brittlestar ID, Brittlestar Behavior, Brittlestar Compatibility, Brittlestar Selection, Brittlestar Systems, Brittlestar Feeding, Brittlestar Disease, Seastar Selection, Seastar Compatibility, Seastar Systems, Seastar Feeding, Seastar Reproduction, Seastar Disease

All sorts of fishes... and many non-fishes will eat juvenile or small Brittlestars. Amphiprion melanopus Bleeker 1852, the Red and Black Anemonefish,

Banded Brittle Star Babies....     11/12/12
I bought my banded brittle starfish about 2 months ago and haven't noticed any strange behavior. I've only seen it a couple of times when I have turned the light on and it immediately went to find cover.
<Typical behavior for the group/Class of Echinoderms>
I got home from a two day vacation and turned the light on to see 2 tiny baby starfish crawling around. (They are about an inch in diameter maybe 3/4 of an inch and very petite) They look exactly like my starfish, same pattern and colors.
I'm very curious to know if she gave birth or if they hatched.
<Mmm, most likely "came from" the live rock>
How many can she breed at a time?
<Dozens... but spiny skinned animals are dioecious... separate sexes... "takes two to tango">
Very excited as I've read they are very hard to get to breed. I'm just curious how many are crawling around my tank! I have read that somethings can look like their babies but I haven't added any rock since I purchased the tank about 6 months ago.
<These things "take time">
Thank you for your time.
<Welcome. Bob Fenner> 

Serpent Star Breeding/Brittle Stars/Reproduction 3/9/12
So I have recently discovered that I have several baby serpent stars in my filter sponge. Is this common?
<Not unusual in developed systems.>
The funny thing is it's the ones that are brown with black circles on their legs. A species I have never had in my tank. Only two shades of red.
<They likely are micro brittle stars usually reaching an inch in diameter.>
Also I have not added a rock of any sort to my tank in well over a year and my last fish was months ago. Thought it was a little weird. Any info?
<Not weird at all, happens quite often if not the norm. I have never owned a brittle star and during weekly maintenance they have virtually encrusted my sponge pre-filter. I just pick them off and return to the tank. They do a good job of keeping the sponge surface clean. James (Salty Dog)>

marine tank, Eel ill from Bristleworm spawning event?  6-10-11
Dear WWM crew, I have 2 questions for you. I have had an Snowflake eel for 6 1/2 years. He was the size of number pencil when I got him. He is now 3 feet long and 1 1/2 inches thick.
He has been very lethargic lately and I was wondering how long do they live?
<Mmm, at least ten-twelve years>
My 6 line wrasse has been missing for a week and I believe he ate it.
Would that make him sick?
Second question. Two years ago I added Bristle Stars to the tank and last week a very strange thing happened. Literally hundreds of Bristle Stars all exited their hiding places at the same time. They climbed to highest points in the tank. They each postured with the center of their bodies elevated away from the rocks and released white mucus in large amounts.
They then went back into hiding. What was that? Thanks for your help.
<Spawning... whatever triggered this, or these sex cells themselves might also be the root cause of your Echidna's malaise. I'd be changing out a good deal of the water, spiffing up (cleaning) your skimmer contact chamber and collection cup, utilizing a bit of activated carbon in your filter flow path. Bob Fenner>
Re starfish spawn  6/13/2011

Thanks AGAIN WWM crew. Your advice was crucial to saving my reef tank. The starfish spawned simultaneously by the hundreds making my corals and fish very sick. Thanks to your quick advice I was able to save them all. You guys are the greatest.
<Well, perhaps close runners up. Cheers, BobF>

Brittle Star reproduction, 3/31/11
I was first introduced to Brittle Stars only a few months ago. I was given a new Red Sea MAX 130D reef tank system (34 gallons, 29 g aquarium volume and 5 g filter volume) as a Christmas gift, lucky me! I bought all of my live rock from the same LFS, but not from the same batch. I do not remember specifics about the rock, but I do know some of it was from the Fiji area, and the rest was from not too far from there. The first bunch of rock was already cured, as it had been in a store tank at least a few weeks. I waited a few days to buy the rest of my rock, because they were having new rock arrive within a day or two. On one of the newer live rocks I bought from there, I noticed a small star fish when I was trying to arrange the rocks in my tank, already filled with salt RO water. That is my first tank, and still my only tank (though I am oh so badly wanting to take on the project of a large reef tank, maybe around 175 gallons, entirely DIY), so being new to my new absolutely all time favorite hobby, I called the store to not only express to them how excited I was to have this awesome hitch hiker, but to also get some help identifying it. Five arms, none thicker than a toothpick, longest arm no longer than about an inch and a half (maybe two inches, as it's known that in a tank, things definitely look different in size), all arms connected through one rather small disk like center, a very light tan color similar to the aragonite substrate with brown stripes (not dark nor light, a very familiar brown color like a crayon), and of course the bristles along all of the arms.
<See here for an overview if you have not already. http://www.wetwebmedia.com/brittlestars.htm .>
As far as behavior, it really did not want to be out in the light. When I discovered it, it fell off of the rock I was moving, and immediately sought the nearest rock to seek shelter in or under. I was told it was a Brittle Star, and possibly because of the size, may be what is called a Micro Brittle Star (though not by much, it HAS grown since I first discovered it, significant yet not drastic keeping in mind over only about three months time).
<Or you have more than one, these are very common and you probably have many unseen specimens hiding in the rock.>
I asked more about it, and learned that it CAN reproduce on its own, more likely to happen if there is much more than enough food available for it, and that it's quite hardy as it apparently survived being shipped with the new rock out of water. Then, about four to six weeks ago, I simply couldn't resist getting a larger Brittle Star from the other LFS which I now prefer of those I have been to. Very similar to my surprise Brittle Star friend, the larger one differed of course in size (longest arm approximately seven or eight inches), and slightly in color (a light brown color with stripes that sometimes seem to be almost a charcoal gray color but at other times brown just like the small Brittle Star). In the past week, its behavior has surprised me. I feel I am very observant with my tank, I can locate just about anything in there visible to the human eye, with the exception of a hitch hiked bristle worm I have only seen twice (once when I discovered it near the bottom on a rock about two weeks ago, and also last week when I did a serious cleaning session in the tank along with about a 75% water change).
<Again you most likely have more than one, they too are very common and hardy.>
However, you don't have to be more observant than enough to know that the Brittle Stars in my tank have never been active in the open when the lights have been on (typical behavior for Brittle Stars as I have learned), to be surprised and excited to see the larger one incredibly active in the light time hours for couple days. Going from side to side in the tank, climbing the glass all the way to the top of the tank a few times, sprawled out just perfect for some pictures (granted the camera used was the one on my cell phone, not to mention the subject of the photos were of course inside a glass aquarium tank), it was a real treat to see it so active. That happened no more than a week ago, and since then, it has remained underneath the rock where the smaller Brittle Star never leaves.
<They generally stay in the rockwork, only really coming out to eat and then quickly returning to shelter.>
I have read that Brittle Stars, as far as reproduction goes, can reproduce sexually, asexually, and through fragmentation. Of course, I've read different statements among various specific species. As I do not know the specific ID names of my Brittle Stars, I have given you the best description I could. If there are more things about the stars I have not thought of that may help you identify them a little better, I would gladly do my best to find answers for you. So finally, to my question (about twenty sentences over due). Would you have any reason to believe, given 1- the surprising behavior recently from the larger star, 2- the physical similarities between the two stars, and 3- the fact that the larger star now doesn't even show more than up to a couple inches of itself at any time from the rock where the smaller star resides, that I may soon discover the stars have made heavenly love (forgive the pun, I just want to add some humor to my enormous message to you, if it's too inappropriate to post online feel free to change it), *ahem reproduced*, and may soon find more Brittle Stars in my tank?
<You very well may find more stars in the tank, but the chances that these two stars are capable of reproduction together is very slim, most likely they are different species.>
Re: Brittle Star reproduction, 3/31/11
Thank you for taking the time to read and reply to my message. Any tips on trying to promote reproduction among brittles?
<Good water quality, plenty of live rock for hiding places, and limiting predators is about it, they will take care of the rest.>

Brittle Star questions, comp., repro.   7/24/10
<Howdy Malcolm>
A couple of questions re Brittle Stars-
Are Brittle Stars better off in the fuge or display?
<Mmmm, tricky. Well, some species are better off for all concerns (ornamental, functional, safety-wise) in either place, and some species, due to size, predatory tendencies... in neither!>
The display is a 5x2x2 community tank with lots of rock. Fuge space is about 1.5x1.5ft coral rubble and macro.
About 2 months ago I bought a lot of livestock from a friend whose tank ruptured. Included was a large Brittle Star (approx 9-10") which I placed in my fuge as a temporary measure.
<Good move>
When I tried to get him out again it proved impossible without dismantling the fuge so I left him alone. During this I thought I might have snapped off a leg but couldn't be certain.
For various reasons I'm dismantling the fuge this weekend so have the opportunity to put him in the display, or back in the fuge when I'm done. What's considered the best place for these?
<What species is this?>
Also how do these things multiply.
<Sexually, asexually... Please read here:
toward the bottom of the page...>
I'm 95% sure I only had one when I put him in there a couple of months ago but there's now two of them. Smaller one looks to be about 4". Can they grow from a broken leg like other starfish?...
It could be that the leg I thought had broken off might have been this second star but I'm so sure there was only one although it could have come in on some macro from the same ruptured tank...
<And you, Bob Fenner>

Another Ophiuroid brittle star mass-spawning observed, and thoughts thereon.   3/21/10
Mr., Herr, Senor B-san and distinguished company,
In my two years or so of keeping marine organisms I have been fortunate to witness sexual reproductive behavior by feather dusters, cleaner (L. amboinensis) and peppermint ('L. wurdemanni') shrimp, an urchin (M. globulus), and a few snail species (with Nassarius and Trochus varieties surviving at least into recognizable subadults.)
<You are observant. A good trait in aquarists, aware humans>
Most recently, I was lucky enough to observe part of a mass-spawning event by a good many Ophiuroid 'micro-brittle stars' in my 75 gallon reef tank and would like to put some comments out there on my observations since a cursory search of WWM and the wider web revealed a relatively small amount of information on the subject.
Specifically, the initial reading I did on the subject suggested that these events are triggered in aquaria primarily by 1) water changes and 2) light cycles (if controlled in captivity). The stirring of detritus seems to rate a distant third as a possible stimulus. I believe in my case the stirring of detritus was probably the primary stimulus responsible for triggering the mass-spawn, even though it accompanied a water change.
The system has a 29 gallon sump and 20 gallon DSB/Chaeto/fuge/surge tank for a total *water* volume of about 100, maybe 110 gallons. I have pretty strong NNR action going in the system along with a decent skimmer, and find that weekly water changes of only 5 gallons or so along with religious partial changing of carbon and Pura-Pads are enough to keep my water quality very high. I have some tougher (to maintain) corals in the tank that I am attempting, and also a lot of not-so-tough to keep stuff that I like to feed fairly heavily since a) my lighting is not blazing bright by any means and b) some of the animals are aposymbiotic. Part of my coral-feeding routine includes regular stirring of the substrates in all of the system's vessels to suspend detritus to be either eaten or removed by pads or the skimmer. Last week I decided to change about 7 gallons of water--a larger than usual change but still small by any reasonable measure, and performed about two and four gallons at a time respectively, on two consecutive days. On the second day of water changing, I decided to also stir up the substrate in the display area very intensely since it had not been stirred deeply in a few months. I then removed the change water while cloudy--this process intended to be first a 'feeding' and second a 'cleaning'. After completing the water change, I went upstairs and had dinner. When I came back downstairs to the tank about a half hour later, I saw the last ten or fifteen minutes of the Ophiuroid mass-spawn. I do the 5-gallon weekly change religiously, usually with light to moderate stirring of the substrate at the same time, and have never seen a brittle star mass-spawn, but this time with the intense detritus stirring I did. This was about 2-3 hours before lights-out and there were no adjustments made for daylight savings time to my lighting yet (the switch was that weekend). I don't believe light cycles had any role in triggering the event at all. The water change cannot be ruled out as a contributing factor, but this water change wasn't much different from lots of others that came before it--except that I made special effort to stir up a lot of detritus at the same time. I would submit that since some stirring of the substrate is a normal part of water changes for a good many aquarists, it stands to reason that a burst of organics in the water column--not any result of a 'water change' per se--may indeed have been the real trigger here all along. Further experimentation that can shed more light on this question should be easy to design and perform.
Another interesting detail is in the nature of the gametes broadcast while I was watching. In every previous spawning I have seen in my systems, the gametes were milky white and 'smoke-like'--presumably sperm. In this case, all I saw looked like (and I assume were) tiny reddish-brown roe--at first glance looking like a 'loose stool' from a fish if you will. Males broadcasting first, followed by the females is reported in this account of an Ophiuroid mass-spawn in the wild witnessed by some lucky divers:
It would seem that my captive event had a similar timeline to that in the wild recorded in the account linked above, and that I caught the tail-end of the females' broadcast. Unfortunately, I didn't get any good pictures of the event, but WWM already has some very nice shots from another hobbyist that pretty much reflect what I saw, and the account of the incident in the wild is also quite good and comparable to my own experience in terms of the visuals provided (they got some nice shots of [apparently] some female roe broadcasts).
My display tank has dozens, perhaps a couple hundred of these small starfish in it, normally only visible for their arms projecting from openings in the rockscape. They came out into full view and stood up for this event. My one large brittle star also had a similar posture up inside the rockwork when I came back after dinner; I think it is possible that it also participated in the spawning with the many from the much smaller species, but I did not actually see that happen.
I can provide more details on system history, feeding, and water parameters if you think it will be helpful but my sense is that they are probably not really relevant here.
Hopefully this account will be useful, and as always, thanks so much for providing this resource. I owe a lot of success to this website.
Take care,
<Thank you for your report. Will post/share. Bob Fenner>

Green Brittle Star…Sick Or Reproducing? - 04/1/08 I have had a green brittle star for 9 months in a 120 gallon tank. It has been healthy & grown well! <<Mmm… Ophiarachna incrassate? Can indeed get large…and is known to ambush and eat fish>> Without any indication of being sick, in a matter of less than 24 hours, it rubbed itself against a rough piece of live rock & sawed itself into 4 pieces (all but one have a chunk of the body on it). <<You actually saw this? Strange…>> How can you tell if it did this because it is sick or reproducing? <<Don't know that you can…though this seems extreme for reproductive behavior>> What are the chances any of the pieces will survive? <<Not uncommon for those pieces with bits of the oral disc attached to grow in to/become whole animals again…in the wild. Not so much…in captivity>> All four are moving about the tank with ease. <<About all you can do is keep an eye on them…remove if they "die" and begin to decompose>> Thanks for your advice. Kristie <<Happy to share. EricR>>

Nature... Brittle Star Reproduction   9/11/07  Good evening crew. <Greetings fellow nature lover.> I had an incredible experience the other day when I came home from church, my protein skimmer was overflowing all over the floor in my house. <Holy water?> We lost about 5 gallons of water, which forced me to do a water change and some tank cleaning. <Yikes! The non-voluntary kind!> When I had completed the cleaning, I noticed about 7 brittle stars (I am assuming the species) <Are micro brittle stars.> had congregated within a colony of button polyps, and others were coming out in other rocks. Within about a half hour of seeing them, they would come to the top of the polyps, would stand up on their legs and started secreting a white liquid from the underside of their body. I am guessing that I was witnessing propagation in progress. <Sure looks like it!> They were gathering in groups and doing this. <Gathering in groups gives a reproductive advantage when broadcast spawning.> I also had two of them climbing the back wall of the tank, one chasing the other and secreting the fluid next to the other one. I have attached pictures of one standing on my toadstool coral and two of the stars on the polyps in a group secreting around each other. I thought this might help others who are seeing this as well and hope that you can affirm or correct my assumptions. <I think your assumptions are spot on. Very nice photos capturing this potentially procreative moment!> Great site and thanks for your hard work, <Is Bob's blood, sweat and tears with many ancillary providers.> its well worth the read when I need the help. <Glad you find it beneficial!

Brittle Star Fish Reproduction? Nope... Micro Brittle Stars - 08/01/07 <Greetings Mich here.> I have a brittle star fish. <OK.> It lost about an inch of two legs a couple weeks ago. <OK.> I saw them wiggling around, but then they disappeared. <OK.> Now I am noticing at least 10 "baby" starfish wiggling around in the crushed coral. I've questioned in the past about the "starfish" attached to the glass (which are not starfish at all). <Likely Asterina stars.> These are definitely different. Their arms move around just like the momma star and they are the exact proportion, but they are so small. Could they actually be reproduced brittle starfish? <No. Most likely a different species altogether. These are probably micro brittle stars (Ophiactis spp.), beneficial scavengers. A fine addition to any marine tank. You can see some photos here: http://www.wetwebmedia.com/brittlestaridfaqs.htm > Why are there so many if only two legs broke off? <Are not one and the same.> Thank you for your help! <Welcome! Mich>

Re: Brittle Star Fish Reproduction? - 08/02/07 Thanks Mich, <Welcome Kristie!> very much understood! <Good to hear.> One more question: What is the likelihood that the broken off legs will reproduce & survive? <Highly unlikely. Generally, some part of the central disc needs to be present for regeneration... I don't get the impression this was the case with yours.> Would the mother star eat it? <Likely something might eat it... all depends upon the critters known and unknown in your system.> I sound so foolish, but I can't find my answer elsewhere. <The only foolish questions are those that aren't asked.> Thanks for you time! <Welcome. A pleasure to share! Mich> Kristie

Brittle star reproduction    5/3/07 Hello Bob, <Michael> I too have twice witnessed a mass spawning of mini brittle stars within the last two months.  Both events occurred after large water changes. It was very interesting to watch (I counted 26 stars).  The first time I got to see the whole event from start to finish... about 40 minutes.  My question is what do baby brittle stars look like? <Like itty bitty versions of the adults> I have noticed hundreds of little almost microscopic critters hanging onto the glass. The bodies are clear and smaller than a grain of sand with several "arms" sticking out.  I would say that as of now they are about 3mm across.  I have been searching the web for images of baby starfish but to no avail.  Do you have any ideas?  I need to clean my glass but do not want to kill any good babies. <Move slowly and they won't be damaged> Thank you, Michael <Cheers, Bob Fenner>

Brittlestar Mass Spawning Event - 01/02/07 I know, you all have answered so many questions about these little buggers that you want to delete this. <<Not at all...>> Please don't. <<No worries mate>> I want an opportunity to add to the community knowledge base.  I have just witnessed a peculiar thing in my tank and I would like to share it with you. <<Please do>>    Earlier today I was adding a refugium to my tank. <<Always a worthwhile addition>> This has become necessary due to the amount of life in the tank and the feeding it requires.  Amidst the addition of the new tank replete with algae refugium I took the opportunity to create a seasonal hurricane for my wards.   <<...!?>> I add a polishing filter to the water in the form of a powerhead with fiber wool style filter material to pick up the detritus in the water column.  Within an hour I noticed the tank had become quite murky which is not a usual condition at this stage.  Upon closer inspection I noticed that all of my little brittle stars (normally quite hidden in the daylight cycle) were sticking their arms out from the recesses and being very visible. <<Possibly feeding on the newly disturbed detritus>> Once I was on to them I really noticed them.  ALL OF THEM!  I think every bloody brittle star was popping out of their hole and showing themselves. <<neat>> I knew I had a lot from the night flashlight spying I often do but whoa!  It was then that I notice the puffs of whitish liquid they were forcing from their bodies. <<Ahh...a spawning event>> This was what was making the tank murky. <<Indeed>> I watched several large (1") stars come out of their hiding place, arch up away from the coral they were in and release this liquid which dispersed into the water.  I can only assume they were performing some mass reproduction. <<A logical assumption>> It is seemingly possible that they were bothered by some chemical released from my "hurricane". <<Mmm...some biological cue possibly...or maybe spurred by the additional water flow...>> Several hours have passed and the water is clear and all the stars have gone back into hiding.  What do you guys think? <<As you suspect...a mass spawning event>> Have you seen/heard of this before? <<I have witnessed such events with gastropods, but have not seen such with Ophiuroids>> Did I see something cool? <<Indeed>> Let me know. Regards,   Andrew Molinaro <<Spawning events of any sort are usually a rare treat in this hobby...relish your experience.  Eric Russell>>

Micro Brittle Stars    4/16/06 I found what looks like about a dozen baby brittle stars hiding in the  green algae in my seahorse tank. I had 2 yellow with green banded brittle stars  in the tank for a short while, but moved the larger one to another  tank. Should I move the babies to another tank / someplace safer? <I think it may be a mistake to jump to the conclusion that these are offspring, they may what most aquarists call "micro" brittle stars, smaller versions of the big cousins that rarely reach over an 1", quite common and good detritivores……..leave them be.> They are about  1 cm across (tip to tip of legs), so I don't think the seahorses will eat them, <It is possible but they reproduce quite quickly, I really wouldn't worry either way, just enjoy.> but there is a fire shrimp in there as well, although I've never seen him in the algae. What should I be feeding them? <They will eat detritus and leftovers, if there is a fair amount of them they likely have a food source.> Would the two starfish reproduce again if they are together, or is this a fluke? <Likely not a reproduction but another much smaller species.> Thanks for any advice. Kim <Adam J.>

Brittle Star 8/11/05 Hello, <Morning> A couple of weeks ago, I bought a large piece of live rock and the next morning I was pleasantly surprised to see a brittle star roaming around my tank.  One morning, I woke to find a small piece of the brittle stars arm chopped off and it is now moving around my tank.  I am assuming it was attacked by an aggressive hermit crab, which I have since removed. I have heard that if a starfish's arm is cut off, it will grow back but I was also told that the arm that was removed will grow into another starfish.  Is this all true or just some hot air? <Often such injuries do result in the growth of a new individual, and the "donor" regenerate the missing part. Bob Fenner>

Tiny serpent stars out of control Hi,  <Hello Christine> I cannot find any reference to anyone else having the problem I have with my tank. All references to tiny serpent stars indicate that they aren't a problem, but....6 months ago 3 tiny white serpent stars hitchhiked into my tank with some Caulerpa. They remain small when fully grown (maximum of 2 inches tip of arm to tip of opposite arm, tiny bodies). They reproduce like rabbits. I have 2 captive bred seahorses, 1 red thorny starfish, snails, several types of worms, live rock, and live sand in a 30 gallon tank.  The serpent stars remain tiny, but have multiplied out of control without a predator. I regularly suck them out with a turkey baster, and pull the fake plants/corals they like to hang out on, and rinse them in fresh water before returning them to the tank. All to no avail. The serpent stars are imbedded in the live rock and the population does not seem to diminish despite my efforts. Tonight, one went for a ride on a seahorse (it actually woke up the seahorse when the seahorse was already asleep) which seemed to make the seahorse itch (she was trying to rub the serpent star off). I helped get it off by using a turkey baster to agitate the water near the seahorse.  I don't mind having some small serpent stars because they are cute and funny and make a good cleanup crew, but this is too many. I am trying to limit the food supply by target feeding my seahorses larger PE Mysis shrimp in the water column and removing the excess (any that falls to the sand) immediately. I started this 1 week ago. Before this I used Hikari Mysis which had so many small pieces that the serpent stars could find Mysis that had fallen to the tank bottom. The seahorses only ate the whole Mysis, leaving the serpent stars with a good food supply. If limiting the food supply will work to thin out the serpent star population, how long will it take? What else can I do, especially to the live rock where they hide, that won't kill the Caulerpa or the beneficial bacteria. One rock has a feather duster worm I would like to keep. I'm considering arranging all live rock at one end of the tank, and only feeding seahorses at the other end. Would that help deprive the serpent stars of food?  <Not really, it will end up in the water column somewhere.> I would appreciate any advice you have. (By the way-water quality parameters are good, so is dissolved oxygen-I'm careful about that).  <Christine, I think you have the perfect habitat for the harlequin shrimp. The feed exclusively on seastars. You may want to give one of these guys a try, keeping in mind that the harlequin does not feed on all seastars, just certain species, but if it were me, I'd give it a try. James (Salty Dog)>

Mini star Breeding (9/14/04) Hi, <Hi. Steve Allen with you today.> My name is Alex and I have been very intrigued by these "mini" brittle stars. None of the LFS in Sac, CA have them, but I have seen them on IPSF.com <I love this place. Shipping is costly, but excellent product.> and eBay. Not sure about the guy on eBay, but he does sound knowledgeable. Anyways, I have an empty 10 gal. quarantine that I used for my FW and it is sitting around. Would this be sufficient for the mini stars? <They need LR and sand and such.> I would like to breed them in their own tank, because I'm not sure what my 12 reef inhabitants would do with them. <I'd be willing to bet that there are mini Brittlestars in your reef already. They hide very effectively. Search your LR with a flashlight after dark and you may see some (among other fascinating things.> I have searched the web (google) and can't find anything on these "mini stars". <They are small Brittlestars, search that way.> What would be the optimal substrate? The LR wouldn't be crazy, as this is not a show tank, but I assume that they need some. Also, most everything like water quality and temp is same for regular brittle stars, correct? <Yes, but like I said, you will seldom see them. Although these are fascinating, you are far more likely to be able to observe the larger stars. These usually never even make and inch in arm span.> Anyways, the big question is, exactly WHAT are their feeding requirements? <detritus> Perhaps pieces of thawed prams? <They do not get big enough for this. The central disk is only a couple of millimeters in diameter.> Do they even need feeding? <In such a tank, they would need some sort of tiny planktonic food.> I have no clue to go about feeding these creatures. Any help would be appreciated. <Personally, I would not expend the resources on a tank just for these stars. Check your reef at night first.> -Alex (14) ^_^ PS, My dream is a shark or Arowana (Asian) tank, estimates how much $$$ I gotta save up? d:D <I'll answer your separate shark query tonight after I can do some research in my books at home, but there are a lot of good reasons to leave sharks in the sea.>

Brittlestar Reproduction (7/28/04) I have some questions about brittle star reproduction. I've had a black brittle star, about 12" from tip to tip, in my reef tank now for about 7-8 months. I recently added another brittle star, mottled brown  12" tip to tip. They seem to like each other (?) because they are always together. <Brittlestars to tend to congregate.> What is the likelihood of having babies? <Hard to say as they may be different species that can't reproduce together. Most are free-spawners and do so seasonally.> Are there ways to differentiate between sexes? <No> I'd love to have more because they are so entertaining. <The best way to get more is to buy more. It is highly unusual or near impossible to get them to survive to adulthood in the confined predatory environment of a tank.> I do have a ton of small white Brittlestars, probably minis. <Yes, fascinating creatures in their own right, and useful too. Much easier for them to proliferate. They reproduce faster and can hide better in smaller spaces because they don't grow to an inch in arm span.> Can you shed some light for me? Thank you!!! <Hope this helps. Steve Allen.>

Where Did This Star Come From? (7/7/04) Hi All! <Hi! Steve Allen with you tonight.>   You've helped me a great deal in the past so I thought I'd give you guys a try on this question! I turned on my tank light tonight and to my surprise - there was A SECOND brittle starfish on the intake to my filter: about 1 and a half inches in diameter (if it chose to be a perfect circle...).  A PERFECT "reproduction" of the one  I purchased in March (he's about 8 inches or so from tip to tip and a scavenging beauty! Spiky but the center is VELVETY MAROON...) <Probably an Ophiocoma of some sort. Nice. Brittlestars are cool.> The little guy hung on by One Tip of One Leg and let go to gracefully float to the sand in a "tear drop" shape to escape the light...so PRETTY!!!  I've NO IDEA where the second one came from:  I know from this site that they reproduce asexually or by "pieces" but the original one never suffered any trauma or "leg loss" so that can't be it...It was a MIND BOGGLING experience - something REPRODUCED in my tank!!! <Or it's a live rock hitchhiker--hard to be certain. I've only known creatures to die previously...(unfortunately, and not for lack of trying). <We've all lost creatures. The conscientious aquarist strives to create conditions to maximize thriving and chooses only creatures with a high success probability, yet sometimes things still don't work out.> However,  I can find ONLY ONE. From what I've read, there should be many others....However, there are none in the filtration. <Could be hiding anywhere or maybe there are none. I don't think you can ever be sure what really happened.>  Will Camel or Peppermint Shrimp eat the little Brittle Star Critters?? <Any number of critters will eat smaller, vulnerable critters if they can catch them.> And is one of this little guy's size in any danger from them? <It should be OK. They are quite good at hiding in tiny spaces. Who knows, maybe there are more of them.> Thanks for your help! Bella

Severed Brittlestar Arm Still Alive (6/23/04) My green serpent star lost an arm about two weeks ago.  The arm (approx.8") appears to be healthy and crawling around the tank on its own. <creepy, eh?> I realize starfish will regenerate a new arm, but will the arm regenerate a new body? Mike B. <Well this has been know to happen, though much more rarely than the other way around. If part of the central disk remains attached, it is possible. I'd say it's less likely than with other stars such as Linckias. There are may pictures of Linckia arms regrowing into whole starfish. When the new legs are still stubby, they are often referred to as "comets." Steve Allen.>

Mini Brittlestars (1/26/04) Hello again, <Hi. Steve Allen tonight> Let me start by saying that you guys are very good at your jobs.  I have a question about a serpent star that I have found in my tank. I have been watching it for about 4 or 5 months now ,turns out there is more then one. My question is are there a mini kind of the family? <Yes> They seem to be a off white color and only about half an inch in size.  In the picture there is a red dot in the centers just up from that is the one that I tried to get a pic of , the dot is only about half an inch for size reference. The smallest one I have seen in the tank in only about a sixteenth of an inch in size. <I can't view the picture because it's part of the message rather than a .jpg attachment. By your description, these are miniature brittle stars. Very cool to have. Some readers of this message are surely envious. If you want more info, you can read more in Bob & Anthony's "Reef Invertebrates" book.>

Lots of small, white starfish Hi Bob and Friends! <cheers!> About four months ago I added a spiny black brittle starfish (looked like Ophiocoma paucigranulata from your photos) to my semi-aged system (about 6 months along at the time). It seemed to be doing well: It was always moving around (mainly at night), arms active at feeding time, climbed on all of the live rock, etc. Several weeks after introducing it into my tank, it started to get very lethargic, and didn't move much. A few days later, I saw my Pacific Tang attack it. The Tang was biting off its spines, and carrying it around the tank. I separated them using a grate that came with my wet/dry filter. A few minutes later, I saw the starfish spitting up small brown spheres. It then picked all of the brown parts away, and there were baby starfish!!! It was remarkable to watch!!!  <wonderful!! Yes, some Ophiuroids are indeed brood spawners> After 15 minutes or so it seemed to be done and I counted 5-6 starfish. They were REALLY small (maybe a quarter inch in diameter), and completely white. That night, the babies all disappeared (I assume they crawled off under rocks). Within the next week, the adult starfish ejected its arms and died from its Tang-inflicted wounds :( So, about a month or two ago, I saw one of the tiny starfish in a hole in a piece of live rock. It was much larger (about an inch in diameter), but still completely white. After a few hours, I found two more. Every day or so, I would check on them and see if they were still around - They were. Then, a week or so ago, I noticed 4-5 starfish hiding in a clump of hair Caulerpa. Every day I would look and there seemed to be a few more. Tonight, I counted 40 of them around the tank (so I assume there to be at least twice that). They're all between a quarter and one and a half inches in diameter and completely white. Other than their color and size, they appear to be identical to the original starfish. My questions are: 1) Do you think they are all from the original black brittle starfish, or just coincidental hitchhikers on some of my live rock? <could be either... brooders expel many more babies than just 4 or 5. So you surely missed some of the spawning activity. However, there are quite a few Ophiuroid stars that arrive incidentally with live rock and sand> 2) What should I do about them?  <enjoy them... they are wonderful additions to the tank> 3) There's a lot of them - Should I be worried about them exceeding the tank capacity?  <nope... they will limit themselves by available food> 4) Is it possible that the Tang would attack them?  <yes, but unlikely... the tang attacked the adult because it was compromised> I haven't seen him take any interest in the small starfish, so I assumed that the original starfish was giving off some sort of hormone as part of the birthing process that sent the Tang into a feeding frenzy. However, I admit to having absolutely no background in marine biology, so this is of course purely conjecture. Any help/advice you can offer would be greatly appreciated. And, as always, my sincere thanks for the IMMENSELY helpful website and books - I actually occasionally feel like I know what I'm talking about!!! <that makes two of us <G>> - Jes PS. Tank info: 75 gallons with at least 100 lbs of live rock (probably closer to 150).Amiracle protein skimmer, producing a lot of disgusting crap every day (and cleaned every day). Amiracle wet/dry rated for 150 gallons (with the pre-filter pad replaced twice a week to keep Nitrates down). Inhabitants are: 1 Pacific Blue Tang 2 Ocellaris clown fish 2 Neon blue gobies 6 blue-green Chromis damsels 1 Flamefish / Dartfish ~ 20 Snails (turbo, Astrea and red moon) ~ 10 hermit crabs (left-claw zebras and blue-legged crabs) ~ tons of starfish Lots of Caulerpa of 4-5 different species (trimmed regularly)(and they're all doing very well) Chemicals: 0 NH3/NH4 0 NO2 5-10 NO3 (depending on if I do a water change after 2 or 3 weeks) <Best regards, Anthony>

Brittle star what astronomical event signals the advent of mass spawning underwater? <Principally the position of the moon, secondarily the sun. Bob Fenner>

Brittle star reproduction/infestation - 6/21/03 I have a huge number of small starfish, apparently brittle starfish.  I am wondering if they are reproducing?  I find them on live rock, in the sand, in the skimmer, in the filter.  My guess is there are a ton of them around my tank.   <many Ophiuroid brittle starfish commonly reproduce> Is this safe?   <they are reef safe, but their excessive proliferation may indicate a lack of water flow or excessive feeding on your part to support them. Perhaps a poorly functioning skimmer or weak water change schedule. Look at nutrient export issues> Are they adding anything to my tank?  Are they beneficial?   <they are excellent detritivores/scavengers> They are all about ? inch in size and there are a TON of them.  Thoughts? Thanks, Tony Jopling <enjoy them... many aquarists pay good money to get these creatures. Kind regards, Anthony>

Serpent Starfish (baby) I found your site by complete accident and found that it has a lot of great and useful information. I do have a question that you can hopefully help me with.  If not, that's okay.<sure its fine> I am a complete novice at this whole salt tank thing, but am completely fascinated and would love to learn more and do it right. I purchased a 55 gallon tank with the works from a friend.  It was already set up and going.  It contains live rock, anemones, 2 snail "things", 4 blue legged hermits, 1 red legged hermit, 1 sea cucumber, 2 serpent starfish and a skunk shrimp.  A couple of days ago I was watching the tank and the shrimp when I noticed a teeny tiny thing that looked just like a serpent starfish.<probably is a hitchhiker one that came with the live rock>  It was smaller than a dime (5 legs and all) and white.  Its legs are just like strands of hair.  Could this be a baby one??<probably so>  I have looked all over the internet but can not seem to find any links regarding this or a starfish this small.  I have been trying to get a picture of it but it doesn't come out of the rock very often and when it does it stays towards the back making it impossible to capture a picture of it. Any help or ideas would be grateful.<yeah... it probably is a baby starfish, good luck, IanB> Thanks and have a good one Michelle

Serpent starfish (babies) Thanks for your reply.   As of this morning, I have now located 2 possibly 3 of them.  Wonder just how many there are....<you tell me lol> Any idea how long it takes them to mature or to get their color?<months> The adult ones that I have are red and brown with dark brown bands.  Interesting creatures.<they sure are> Again, thanks for your help.  There just isn't much out there on them. At least not that I can find.<yeah they are very young, enjoy> Have a great one. :-)<you too, IanB>

Brittle stars - 10/2/03 hello, I saw something pretty amazing yesterday in my reef tank that I was hoping you could comment on. <OK>  About a year ago we had a brittle star (only one) that eventually wasted away and died (i.e. tips of its arms falling off first and then disappearing). <Sounds horrible (if you were a brittle star)>  Last night there were three tiny brittle stars about the size of my fingernail (from one tip of an arm to another) between the front glass and the crushed coral. <Not sure of the species per se but these are quite common. Likely close to full size, my guess>  Their body is about a millimeter across!  They look exactly like the original brittle star. <are they white or colored? Usually white in color. They seem to bury themselves in mud and eat detritus. Mine seem to find various homes in my liverock structure>  I was wondering if there's a simple explanation - i.e. how do brittle stars reproduce and have these 'babies' been in my tank for the last year? <Maybe in the tank the whole time but you are just noticing them. Have you added live sand recently or even recently added rock or coral. This is how I received mine>  Can brittle star eggs remain unhatched for an extended period of time? <I believe it is possible.> I'm very surprised that they would be so small considering at least one year has passed. <Again, likely full size. -Paul> Thanks, Ben

Yellow brittle star 12/30/03 What a great site...full of wonderful information!  Hoping you can help.. <Thanks!  Me too!> I have a yellow brittle star that has been living in my 80 gal tank for nearly 2 years.  It has grown significantly and is about 18+ inches tip to tip with the body being about 1 3/4 inches across. <Yowza!  Your biggest concern should be that it will crawl out of the tank at night and make off with the neighbors dogs, cats or children!> I haven't changed anything or introduced any new fish in many months.  5 days ago I noticed a small hole in the back of my starfish that is getting bigger daily.  It is about 1/5 the size of his back.  His arms look fine at this time.  He has been very active and appears to be feeding.  My water quality is good and I faithfully do 15-20 gal changes 3 times monthly. <I'm not really sure what this could be, but it is a good sign that the animal is active and feeding.> I do not have another reef tank, but I do have another 30 gal salt with only 2 fish I could possibly move him to in order to medicate if needed.  Any suggestions for me? <I would tend to try to let this run it's course.  Echinoderms are so sensitive that I would only use antibiotics as a last ditch.  There is also the problem of knowing what your are treating and if antibiotics would be effective.  The use of antibiotics is not to be taken lightly!> Thank you in advance for your time, good help is so hard to find! <You're welcome, and I am sorry for not having more definitive or optimistic advice, but invert diseases are extremely difficult to treat.  Adam> Sherri Melting Brittle Star 2 Hello Steve, Please take a look at this photo, should I leave the star in the aquarium? Will treating him separately help in regeneration? He is currently hiding under a rock. Regards, Samir <Samir:  Sorry to see that your brittle star looks so terrible. I would say there is virtually no chance it will survive because of the severe damage to the central disk. I would not leave it in the tank because its gradual death will degrade your water quality. If you want to try to treat it with antibiotics in a QT, you can; but I'd say it's chances of survival are minimal at best. Sorry, Steve>

Every Event a Lesson (12/29/2003) Thank you very much, I do really appreciate your input. I guess I just got a hard learnt lesson. <I was sorry to hear/see your troubles with this Brittlestar. The tough part is that it's hard to say what caused it. Do read up on these creatures. I heartily recommend Bob & Anthony's "Reef Invertebrates."> I hope it makes me a better aquarist? <Every lesson learned from experience or reading will make each of us a better aquarist. The painful ones are the longest remembered.> Will keep looking at WWM <Believe me, you will learn something every day that way.> Thanks again Happy Holidays regards Samir  <Same to you. Steve Allen>

Reproduction in serpent/brittle star Hello Mr. Fenner, I was checking out the FAQ's on brittle/serpent stars and didn't see what I was looking for. It said that reproduction is sexual and fragmentation. I have a serpent star (small beige with tan stripes) and there seems to be something moving inside of it. Occasionally it swells and then these bumps appear to be swirling around inside of the body. When this is not happening it still appears "larger than usual" and the edges of the body seems to have something pushing outward. We first noticed it about 3-4 weeks ago. We have seen this star intermingled with another (light green, dark stripes) and didn't know if maybe it was pregnant. Any information is greatly appreciated. Thank you- Joanne Nobre <Hmm, interesting... could be developing gonads you're seeing, or a waxing/waning tumor of some sort, or a parasite... Keep a keen eye on it. Bob Fenner>

Strange starfish pests Hi Bob... <You actually reached Steven Pro working his shift answering queries at WWM. Anthony Calfo and I are helping out for the time being.> I have been noticing lately while cleaning my 55 gal reef aquarium, that I have an abundance on small (1 centimeter or so) white critters that look a lot like serpent starfish. The perplexing thing about this find is that I have no serpent stars in my tank. I have an overflow filter that seems to catch a bunch of these things in the filter media and have also seen them cruising across the rear glass in the morning when I turn on the lights. Are they something I should be concerned about? They seem to be multiplying rather quickly. <They are nothing to worry about. You are correct, they are tiny serpent starfish. They are not babies, but miniature adults that are brooders and are quite prolific. They make excellent scavengers. -Steven Pro> Carrie

Brittle Star Question. A few weeks ago I bought a brittle star for my newly cycled reef tank. I had two damsels and a chocolate chip star in with it. One day I came across my brittle star in full daylight sitting on my highest rock in the tank with all his arms sticking straight out. Also, he was excreting a white liquid into the water.  <from where did it originate? Assumedly from under the center of the body?> He has all his arms and no cuts anywhere. What is he doing and will it contaminate my tank?  <not clear just yet, but no it is not toxic and it will not contaminate your tank unless it is dying/rotting. I assume though that it moved on?> I'm willing to get rid of him because I mysteriously lost both damsels about a week after that. Thanks, Laura <yikes... easy on the knee-jerk reactions, my friend. I'd hate to be a bad child in your house <smile>. One strike and you're homeless! Hehe... I'm sure the starfish dis not kill the damsels. And if the starfishes behavior was related at all... it was due to the fact that whatever stressed and killed the damsels could have stressed the starfish first in to behaving so. Since it is a new tank.. have you confirmed that your chemistry is/has been stable? When in doubt, do a water change. Best regards, Anthony>

Brittle Star Question. Thank you for emailing back so quickly about my brittle star question with the white secretion it was emitting.  <my pleasure> I work for a pet store, so I'm pretty informed on a few things concerning brittle stars, but no one at work knew what mine was doing. I finally contacted the seller and he informed me it was a green brittle star (the ones notorious for sneaking up on sleeping fish).  <Arghhh! O. incrassata, the wily devil!> I traded him in for a safer cleaner... a hermit crab. So thanks for your quick response! For future knowledge, what was the white stuff my brittle star was emitting? It looked like it was coming from under his disc and he was doing it for at least a half an hour. Possibly sperm?  <possible but not likely eggs/sperm. More likely the product of digestion. Many echinoderms graze aggressively on the rock surface and pick up calcareous material (corallines, etc) to digest the organic material off of them (algae, bacteria, crustacea, etc)... the indigestible material is simply discarded. My educated guess without having seen the event I have no clue and everyone at the shop wants to know! Thank again! Sincerely, Laura <best regards, Anthony Calfo>

Become a Sponsor Features:
Daily FAQs FW Daily FAQs SW Pix of the Day FW Pix of the Day New On WWM
Helpful Links Hobbyist Forum Calendars Admin Index Cover Images
Featured Sponsors: