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FAQs about Sea Stars 2

Related Articles: Sea Stars, Brittle StarsAsterina Stars, An Introduction to the Echinoderms:  The Sea Stars, Sea Urchins, Sea Cucumbers and More... By James W. Fatherree, M.Sc.

Related FAQs: Sea Stars 1, Sea Stars 3, Sea Stars 4, Sea Stars 5, Brittle Stars, Seastar ID 1, Seastar Selection, Seastar Compatibility, Seastar Systems, Seastar Behavior, Seastar Feeding, Seastar Reproduction, Seastar DiseaseAsterina Stars, Chocolate Chip Stars, Crown of Thorns Stars, Fromia Stars, Linckia Stars, Linckia Stars 2, Sand-Sifting Stars,

At right, an Orange Marble Starfish (Fromia monilis)

Nuisance sea stars (Asterina) Hi, and thanks for your last reply on the length that I can keep mixed Kalk. I am now becoming concerned with the eradication of the dreaded tiny starfish that can get up to the size of a dime that I have had in small numbers in my tank for approximately one year.  <I assume that they have not eaten anything desirable, but that they have simply grown to a nuisance population?> I continually find them everywhere and have removed upwards of 200 from my tank over the same time period. The starfish have only been on one side of the tank but are now migrating to the other and I am worried about my SPS corals on that side of the tank.  <my friend... at these numbers, if the species hasn't eaten a coral yet, they are not going to. Most aquarists never have a single problem with this species... only a few honestly do. They are just a plague... not much of a predator> I have a 180 gallon. Will the Harlequin shrimp take care of these if I can find one or two?  <yowsa! This is an obligate feeder. It may eat the stars... but what happens when the stars are eradicated? Are you willing and prepared to buy live starfish monthly if not weekly to keep the shrimp (s) alive? I would never recommend that you simply put a Harlequin in this display for this purpose alone of even primarily. Harlequin shrimp need specialized and direct care> Would I need to keep two or more for the shrimp to feel at home? I don't think I have any fish that would hurt the shrimp. I do have emerald crabs which have never hurt anything that I have so far.  < "so far" being the operative phrase in that sentence... wait until they grow to sandwich size and the cat goes missing> Would I need to remove my sand sifting starfish or wouldn't the harlequins bother them?  <the Harlequins will likely bother your other sea stars> Any other ideas for ridding my tank of the pest starfish?  <dedicated ,manual extraction if they must go... else they are truly excellent algae eaters from the glass (and rocks). You will notice once they are gone> Thanks again, Jeff <kindly, Anthony>

Starfish or Not? I have a reef tank....lots of coral....few fish. Last night on the glass, there was what appeared to be a baby starfish.....although it has 7 legs. <one of the wonders of reef tanks/live rock... many fascinating microorganisms> We took it out of the tank since we recall hearing that this is a potential risk to the corals..... <please don't make a habit of doing that my friend... the overwhelming majority of creatures that you find will be harmless or likely even beneficial. In fact, even the "worst" nuisance animals can easily be controlled via natural predation. My advice is to leave all alone... let it grow, let it grow, let it grow :)> do you know anything about this? <could easily be a seven legged starfish... > Heather <While you are waiting for the WWM "Reef Invertebrates" book to come out <wink>, please check out the following sites for such oddballs http://www.reefs.org/hhfaq/pages/main_pages/faq_rock3.htm http://www.rshimek.com/odd_critters.htm kindly, Anthony>

Q re: Chocolate Chip Starfish Hi~ I recently got a Chocolate Chip Starfish - have never had any starfish before.  <This is a very hardy starfish although not reef safe> He seems to be doing very well, but I've noticed when he's moving around on the glass, he sometimes leaves behind what looks similar to a hair with bubbles on it, only it's not floating around, it's usually stuck to the glass or the top of him. Do you know what this is? <no idea my friend but does not sound handful at all> Also, can you tell me how starfish reproduce? <asexually by vegetative fission at least. Not sure beyond that (internal brooding of planulae perhaps?> Thanks! ~Jami <best regards>

Starfish what are these starfish doing?  HREF="http://www.calacademy.org/research/izg/echinoderm/images/linckia.jpg"> http://www.calacademy.org/research/izg/echinoderm/images/linckia.jpg</A> <A HREF="http://www.nmnh.si.edu/iz/echinoderm/1999/images/comet2gif.gif"> http://www.nmnh.si.edu/iz/echinoderm/1999/images/comet2gif.gif</A> <A HREF="http://www.coralreefnetwork.com/stender/marine/echinoderms/stars/multifora.jpg"> http://www.coralreefnetwork.com/stender/marine/echinoderms/stars/multifora.jpg <Growing. Regenerating from an existing limb... Starfishes that have been bitten off from the middle portion of their bodies... sometimes/places termed "asteroids" by their shape. Bob Fenner>

Keeping Astropecten Hi, <Hello> Thanks for your reply. How can I know the sexes of the specimens I get without dissect them?  <All Seastars, indeed all echinoderms are dioecious, separate sexes... but as with almost all spiny-skinned animal species, this one cannot be sexed by external characteristics. There are no structural or color differences externally between males, females.> I need to observe the gonads of Astropecten monacanthus in each sex. <Oh! You can, could try soaking the specimens as is done with urchins. Please see: http://zoology.unh.edu/faculty/walker/urchin/altering.html Ones that are not atretic, are mature should produce gametes...> In the field, how do I take exactly 4 samples ( 2 males, 2 females ) of Astropecten monacanthus? <I'd gather a few more, test... return extras.> Can this species survive in an aquarium with sandy substrate and feed them with oysters? <Listed as "aquarium hardy" by Baensch, others... I would expand the food selection to include local gastropods> I wish to study the reproduction cycle but I have no idea how to keep them for a long time and what make them mating naturally and spawning.... please help, thank you very much. Karen <Please read here: http://www.wetwebmedia.com/litsrchart.htm re literature searches. I would "do" this now while developing your model, thoughts re how you might conduct your experiments. Bob Fenner>

Re: Keeping Astropecten hi, <Hello> I'm a starfish lover and now studying for diversity of asteroids in Malaysia. I couldn't afford my own reef tank thus cannot keep any of the beautiful starfish. But, I found many sandy and muddy beaches in Penang that abundant with sand stars (Astropecten monacanthus). Does it possible for me to keep them in an aquarium with sandy and muddy substrate and feed them with oysters?  (They feed on small bivalves and gastropods in their habitat.)  <Worth a try... these paxillosid Seastars also eat sea urchins, other sea stars and brittle stars...> What parameters should I concern to make the sand star healthy?  <Pretty much the husbandry generalized here: http://www.wetwebmedia.com/seastars.htm> Kindly seek for your advise and looking for your reply. Thank you very much. All the best in your job. Karen <Thank you my friend. Be chatting. Bob Fenner>

Red Linckia Starfish? Hello is there such thing as a red Linckia? <Probably Echinaster luzonicus or a Fromia sp.> I just bought one but can't find any info <You didn't just buy something you didn't know how to care for, did you? Don't make me yell at you. :) > looks just like the blue Linckia but red. Any info? <Take a look here http://www.wetwebmedia.com/seastars.htm I usually just let my blue Linckia eat whatever he finds, but I occasionally feed him a piece of frozen Formula food.> Thanks in advance <You are welcome. -Steven Pro>

Starfish Troubles Hello WWM team! How r u ? <Doing just fine!> I have a problem that I don't know what's happening. I have a starfish, I don't know which one it is but its not really big, grey with a little bit of white.. seems to be popular because they sale it everywhere.. <Sounds like a serpent starfish.> Anyways, I notice this morning during my water change that the starfish was smaller than usual so I took it to have a better view at it and all is 5 point of the star look like if it as been eaten by a fish or in decomposition or something like that... but it still move like before and still looking in shape. I only have 5 damsels in the only fish tank and the star fish .. can it be the damsel that cause this? <Probably not the cause.> Is my starfish is dying? <Maybe> Can I do something to help the problem? <Anthony went through a dipping procedure for starfish with the same symptoms that you describe. Perform a Google search for starfish and iodide/iodine and you should be able to find it.> Can it be the nitrate that does that.. the level is a 20 ppm? <That does not sound bad at all.> Is there something except, ammonia, nitrite, ph, kH, GH, nitrate, phosphate that need to be check for a starfish? <No, that is a pretty complete picture.> My feather duster died 2 weeks ago too and I don't know why. All my things have no trace except the nitrate that is not really high? anyways... help me pls.. I don't want to lose something else. <Not sure if the two are related or not, but a good water change is almost all in order.> i.e: Can I add a flame angel with a damsel or should I get rid of the damsel before adding some most sensitive fish? <I would get rid of the damsels, more trouble than they are worth. -Steven Pro>

Fromia emission <Anthony Calfo again in your service whilst Bob has interrupted his tour of Australia to get permed hair extensions to join up with the REO Speedwagon reunion tour as a groupie. Some things just defy explanation> First let me say thank you for all the help you've already provided, here on the net and in your book.  <my pleasure and thank you!> I have a situation that I have been unable to find information on so I am sending this email. I recently purchased an orange Fromia star, and a few days after introducing it to my tank I noticed a white cloudy emission coming from spots between its legs where they meet (this is occurring in at least two separate spots.) This emission continues for minutes at a time, and then stops. The star is quite mobile, is eating, and shows no signs of wasting away or dying( that is if the above is not such a sign). So my questions is what do I do...Remove it now? Watch it for a while (and if so what am I watching for)? Any help here would be hot!!! Thanks again. Kris <Kris...it is not perfectly clear to me from the description exactly what is transpiring... however hear are some thoughts. If the spots where the emissions are coming from are not necrotic (no worn or abraded patches) then there may be little cause for alarm. Many echinoderms ingest some coralline and carbonate material while gazing and "spew" it after organic material is dissolved. With normal motility from this star it sounds like it may be OK. Have you noticed it scavenging any frozen green or meaty fares offered (Formula II, shrimp... even dry shrimp pellets)? That would be a fine sign. Please do a keyword search on this site too for Fromia questions in the archives and in articles for perhaps additional enlightenment. Kindly, Anthony>

Tiny Little Starfish Hello all, or rather, whoever ! I had moved my 55 gallon tank a month ago and everything is pretty much broken down. Various fish are in different tanks all through the house, all inhabitants are doing great in their little vacation homes. My concern is this: The main tank which just has a lot of my live rock and live sand in it is infested with tiny little whitish, bluish starfish. I have had a few of these guys from the beginning but never so many like now. The tank has about 40lbs of live rock in it, about 4 inches of live sand, lots of brittle stars, macroalgae, etc., but no fish. I have read some things on these little guys, and I know they supposedly eat coral, don't have any of that, so it doesn't really matter (but will in the future), but I just don't want them in there and refuse to kill them. Is there some fish or such I can get to eat them? Do you know of any damage they may cause? <Without a picture, I can offer you a few good guesses. First, I bet the starfish are harmless. They allegedly eat coral, but you have none and they still reproduce and thrive, so I think they are probably eating something else. Secondly, they are reproducing without fish in the tank. Again, it makes me think they are eating something that the fish would normally eat and compete against them/starve then down in population or whatever fish you have may eat some of the starfish. I would not worry about them at this point, but do try to make a positive identification. Take a look in Julian Sprung's book "The Invert Guide" and Dr. Shimek's "Key to Identification" found on his webpage.> Also, I made my own protein skimmer (countercurrent flow, airstone driven). Since the filter system is broken down right now, I was thinking about changing it to Venturi driven. Is this more trouble than it's worth? <Generally less maintenance than CC air driven models, but far more difficult to DIY.> Do these things really run better than with airstones? <Very debatable. If you are getting good production now, I would be inclined to keep the current unit.> I sure go through a lot of airstones and thought it might even be more cost efficient over time. Whatcha think? <Airstones are pretty cheap. It would probably take years to recover and money saved in airstones versus the pump and Venturi valve to run the new DIY skimmer. Upon rereading, I am not sure you wish to DIY. If not, I would look through the FAQ's on skimmer selection for various recommendations for various size tanks and applications.> Thanks for all the advice, and have a good weekend, Jana <You are welcome. -Steven Pro>

Chocolate Chip Starfish II Hi Bob. <Not Bob now or previously. Bob is off in Australia and the rest of the WWM crew is picking up the pace.> Thank you for your quick response. Why do you say chocolate chip starfish should not be acclimated to brackish water? <I would not recommend any animal be kept in unnatural conditions. Even though aquariums themselves are unnatural, but...> And, are their any starfish that I can acclimate to brackish water? <Not really. Do you have some reason for wanting to do this? -Steven Pro> Thanks, Ashley

Chocolate Chip Starfish III Steven- Sorry about calling you Bob. <No problem, I just wanted you to be clear who was giving you their opinion.> I know its not the ideal situation but, can the chocolate chip star live in brackish water? <I doubt it. Most inverts do not tolerate temporary lower salinity treatments for parasites, so I do not believe it would handle long term conditions.> Unfortunately we already have one, the people at the store said they could be acclimated. <I would return it and ask them if and when they ever performed this feat. I always question the opinion of someone looking to profit from their advise.> It is a small one, less than two inches across. We have no coral in our brackish tank. If it does live what can we feed it. <Variety of prepared frozen foods.> Thanks for your time. Ashley <You are welcome. -Steven Pro>

Guppy and Starfish Questions Hi there! <Cheers.. Anthony Calfo in your service> I seem to be emailing you on a weekly basis these days (sorry) but the more we get into this hobby the more strange and unusual things happen! Anyway, my first question relates to our tropical tank. One of our guppies has got the hots for a silver colored platy.  <what a cheeky little monkey> He pursues her around the tank relentlessly, trying to make her see just what a God's gift to fish he really is, while she plays hard to get! I assume that this relationship is doomed and he will suffer forever from unrequited love.  <are you still talking about fish  or do you know my high school sweetheart?> However, if they do manage to get it together what will the results be? Gatties or Pluppies?  <actually a fish that looks like Buddy Hacket with a tail> Or could there be another reason for his amorous advances? <sure... he may just wants to cuddle...hahahahahahhahhahahhahah! Ahem, I mean...no, I think you've got the general gist of his intent. They may not even be able to produce viable offspring/hydrids> My second question relates to our reef tank. One of our Fromia starfish seemed to expel something from its underside the other night. It was orange in colour (same colour as the starfish) and resembled two hands (or two starfish even) stuck together. It measured about 0.75cm wide and 0.5cm high. It was carried around in the tank by the current and settled briefly on some live rock before disappearing into the reef. The "legs" didn't appear to move during its brief stay on the live rock. Have you any idea what this thing is? <under stress...some echinoderms do release part of their innards. Perhaps this is the case, but I honestly have no clear idea> This hobby just gets more and more fascinating! Thank you for all your help! Lesley <kindly, Anthony>

Purple Linckia Have a 3" star that I got at local pet store 3-4 weeks ago. It has 6 legs, but from your description & pics on your sites, it is a purple. Has been spotless & active. Anyhow, 3 days ago I noticed a tiny mass of dingy white, translucent stuff on the top of its central disk. Star is so small that I'm not sure, but it seemed to have been attached to its madreporite or its "anus". The following day it had developed a few very small white spots on 2 of its legs close to the central disk, and yesterday I saw that there are real small areas of missing flesh (vacu...something?) around these spots. No rotting flesh...yet. It's still active as ever, but has pretty much lost use of its worst affected arm. After reading other e-mails to you, I don't have much hope. And it was so dang adorable! Thank you for you time...Tammy <indeed...bad signs. You might try abrading the soft tissue areas in a bucket of seawater (then disposing) with a soft toothbrush. A short dip with reef iodine at double dose might be therapeutic too. Focus on very good water quality (skimming, water changes, chemical filters) and lets hope for the best. Anthony>

Sick Starfish Hey, My starfish I got from a online over night delivery place came today and it has been in the tank for just around 7-8 hours and it looks like 2 of the legs got caught in hair algae or are falling off.  <Falling off is far more likely due to shipping stresses or damage when bagging or poor acclimation procedures or etc.>  I don't know what to do. <Nothing much to do other than watch and wait. The missing arms can grow back. When a starfish dies, they turn to mush.>  The starfish seems healthy and actively wandering the tank. also I wanted to know if you could tell my why an emerald crab would eat my coral banded shrimp. <Because Emerald crabs are an opportunistic omnivore (that means they will eat whatever, whenever they can).> (I think the crab is carrying eggs) Thanks for your help - Brandon <You are welcome. -Steven Pro>

Blue Linckia Starfish and Beer Bob, <Anthony Calfo in your service while Bob conducts research in Australia to determine if the cans of Foster's Beer are really as large as they look in the commercials> Hi, my name is Lily, I got your email address of the internet because I was searching for information on the blue Linckia starfish for a school project. I only need to know how the Linckia reproduce. If you could give me that information, that would be great, <hmmm... egg-laying not livebearing, but I'm not certain if they brood them internally, lay on substrate or broadcast> if you know anything about the green brittle starfish, or if it really exists, could you give me that information to. <yes... exists! Hardy in aquariums but is uncharacteristically aggressive for a starfish. Will catch and kill small fishes and other invertebrates when they sleep. A Bushwhacker! Ophiararachna incrassata> Thanks so much, Lily Siebert <quite welcome, my dear. With kind regards. Anthony Calfo>

Starfish <Anthony Calfo in your service while Bob makes his way to the great continent of Australia. No worries in travel other than the full cavity searches at every stop along the way (not mandatory... Bob volunteers for them)> Quick question for you. I just added another sand sifting starfish to my tank. I currently had one. Immediately the new one went over to the old one and has been laying on top of it since (about 12 hours). Is this something I need to be concerned about? <a little strange, but likely nothing if they are the same exact same species...else separate to inspect for aggression (inverted stomach thingy)> Thanks for your help! Also, do you recommend a good site that has care information on corals. I'm just beginning and do not want to buy something that I'm not ready for. Victoria Notz <a lot of anecdotal information on the web...much of it good, but can be misleading. My best advice would be to find a local (and online if necessary) aquarium society. These clubs are the absolute best place to get free and honest information from people who are not trying to sell you something. Next, I'd get some good books. For the newest information, I like Borneman's Aquarium Corals and Tullock's Reef Aquarium books. Delbeek and Sprung's Reef Aquarium (1 and 2) are also great old standbys. And shamelessly, I must admit that I have a reef text available as well, Book of Coral Propagation. Much info (450pages) in a conversational tone. Do start with aquarium club... if you don't know of one, let us know your city and we'll apprise you of the closest one. Kindly, Anthony Calfo>

Lost Linckia complications Anthony, Thanks for the response, can I ask one last question?  <please do my friend> Once again I had a giant Linckia disappear, I have a feeling this is trashing my tank, I lost a black urchin, I have a Turbinaria who's polyps were always out, not they are completely retracted yet they occasionally come out, once more I have a giant feather duster who's feathers are now thin, not extended. I am wondering if my best bet would be to break the tank down, and replace 1/2 water with new, It is going to take forever to get nitrates down by 5 gallon changes.  <yes... I would agree... the tiny water changes are just not enough. A properly conducted large water change (adjust pH, temp, SG, aeration, etc carefully to match main display) can bring serious relief fast and is the lesser of two evils so to speak> I also have a Singapore angel who I thought was harmless, until I caught it taking chunks out of my meat coral, if its eating this, it may be picking on others, so I need to remove this fish anyway.  <yes... definitely. Dwarf angels are notoriously dangerous... few work long term in reef aquaria> One other point, I have a purple tang, the angel, and 3 smaller damsel sized fish, I am wondering if I would not benefit by eliminating one of the smaller fish as well, this would help lower trates. What do you think? (The tank is a 55) Thanks again, Tom <removing the small fish will not help much, unfortunately. The single best thing for nitrate control after water changes and deep sand beds is aggressive protein skimming. Make your skimmer work better or consider a second unit to compliment the first (and clean them alternately for uninterrupted skimmate production). Best regards, Anthony>

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