Lynden
a "fish hater"
I see lots of posts recently asking about starfish, that is, what they eat, compatibility, et cetera. This topic will therefore, on the request of Steelhealr, give a quick rundown, by genus, or "type", of the most commonly purchased/encountered in aquaria stars, giving such details as aquarium survivability, hardiness, and dietary needs/compatibility, in the classes Asteroidea and Ophiuroidea (brittle stars). I will refer to both brittle stars and asteroid stars as "starfish".
I will also include a simple 'rating' for each star. A '*****' indicates a very hardy and easy to feed star, whereas a '*' indicates that few people have had any success keeping them for periods over a few months. Also a 'C' indicates that the star feeds on visible ornamental fauna and is thus "un-reef-safe".
All starfish (and all echinoderms for that matter) can go a long time without food. I suspect that most aquarium "for no reason" deaths result from lack of food, leading to the star slowing to a stop over a period over a few months, followed swiftly by death.
First a general description.
All echinoderms follow a pattern of penta-symmetry (five sides that are all the same). They move via a system of tube feet: the thousands of tiny sticky pads under the animal. Their vascular system is hydraulic. There is no circulatory system and all gas exchange is accomplished by simple diffusion.
Starfishes typically extrude their stomachs to envelope food and digest it externally, whereas urchins have five strong teeth that are self-sharpening and used to grind apart foods.
A note often brought up is acclimation times. I cannot speak with any experience on this subject as my brittle and choco chip (got them at the same time) both fell over in the tank after fifteen minutes and they lived until the tank crashed (due to outside causes) several months later. It would be safest to drip acclimate the animal over a period of an hour. Use a bucket, and place the star on a piece of live rock so that it doesn't need to be detached from anything when it is ready to be placed in the tank.
Selecting a healthy specimen is important. An active animal, with no obvious infections/infestations, or lesions on the skin, is good. A missing arm need not disqualify a specimen from purchase, unless the injury site appears to be necrotic. If the store will do so, ask them to place the animal on it's back, and see if it's able to right itself; specimens that cannot may lack the stamina to be taken to a new environment.
On a similar note keep water quality as high as possible. That means biweekly water changes of fair proportions (25% in my case), no ammonia/nitrite, and as little nitrate as possible. While it is true that many stars can be hardy, it is best not to take chances, especially since changing water isn't much work.
Lastly, though I consider this article a good source (though decidedly short), it is always best to research from many different sources. Do read the links provided if you are looking at purchasing any starfish.
Species profiles (Asteroidea)
Protoreaster (such as chocloate chip, and red general); *****, C
Red General, P. lincki - photo courtesy of wikimedia.org
Chocolate chip, P. nodosus - photo courtesy of wikimedia.org
Size: Chocolate chip stars can occasionally hit 8'' if given time and adequate food, and red generals can grow even larger. These stars do not need as much room as similar sized microfauna eating stars do, but I would suggest nothing short of a 75 gallon for a full grown red general, and at least 55 gallons for a full grown choco chip. With that said, they can be kept in slightly smaller quarters (though not ideal) and baby sized ones can be kept in tanks appropriate to their size, even nano tanks for a time.
Feeding: these stars are voracious omnivores. They will eat anything they can catch, even fish from time to time. It would be wise, therefore, to include them in fish-only tanks with large, wary fish such as angels or Anthias.
Feeding should consist of offering 'bite' sized pieces every other day or so. Suitable foods are silversides, shrimp, squid, clams, and anything other sea-faring food fit for human consumption. Good ways to offer the food is to shove it into a rock crevice; put it in the same place every time, and the star will learn to go to that place when hungry. Nori can also be offered.
Compatibility: large, nippy fish, such as Thalassoma, Coris, and Novaculichthys wrasses, plus the largest of benthic triggers and puffers, are all capable of killing a Protoreaster. Avoid housing the two together unless both are very well fed and the fish was purchased at a young age. Apparently very few predators will eat these stars, however. (1)
Archaster, Astropecten, Sand sifting star; ** - photo courtesy of liveaquaria.com
Size: these guys can reach a foot in diameter, though they will probably remain smaller. They need a wide, shallow (as in vertically) tank of preferably a few hundred gallons. Need large amounts of sand and little rock, and can denude tanks of microfauna when large.
Feeding: the hardest part. Will eat anything alive in the sand bed, and they tend to be hyperefficient, clearing even seemingly large tanks of food in a few months. It remains to be said if they could eat food placed in the sand bed, but perhaps it would be a good idea to overfeed the tank on a regular basis to breed prodigious amounts of microfauna. Of course keep up with the water changes.
These animals are hardy for the most part, the only real concern is feeding. Highly compatible with most other livestock, but large wrasses and large benthic tetraodonts are capable of digging up and killing these stars. Shouldn't be too much of a problem.
Fromia (such as peach star, Indian star, marble star); *** - photo courtesy of liveaquaria.com
Size: Fromia are among the smallest of ornamental starfish and as such are much easier to provide for than most. According to liveaquaria, the pictured species only reaches 3'' in diameter. (2) Should have a tank of at least 40-50 gallons with as much live rock as is aesthetically acceptable (for one adult specimen).
Feeding: eats tiny creatures and algae. It will help the star if one were to allow "pest" algaes to grow, as these will harbour an enormous amount of 'pods and other microfauna. Still, it is best not to have any other microfauna eaters in the tank and these would include mandarins, fairy wrasses, pipefish, etc. Though if one attached a refugium to the tank, it would probably work.
Compatibility: large puffers, benthic triggers, and large wrasses may try to eat this star. The star itself typically leaves ornamental animals alone.
True Linckia (such as the blue star); ** - photo courtesy of wikimedia.org
Size: these stars can become quite massive, sometimes (but very rarely) reaching 15'' in diameter. A medium to large specimen, about 5-6'' in diameter, will need a large tank with a huge amount of live rock. A full-grown specimen (13-15'') should be provided with nothing short of a one hundred gallon tank, with as much rock is as aesthetically acceptable. I have heard the minimum for these species varying between seventy five to several hundred gallons.
Feeding: as above must be given a large amount of live rock. The true feeding needs of this starfish are poorly understood, but it would appear they are largely bacteria eaters, undoubtedly with some algae and microfauna included. Therefore the very best way to keep them fed is with live rock and slight overfeeding of the aquarium, but feeding can apparently be supplemented, if one uses very tiny foods (such as mysis fragments or brine shrimp) and makes absolutely sure that the star grasps it. I suspect that this alone will not keep them well fed forever, as one point being they are often unreachable in the reef tank. (5, contributed by tat2life)
Linckia are often damaged in collection, and it would appear that up to ninety-five percent of them can be damaged beyond recovery. (3) It is very important one selects a healthy specimen; one that is active and rigid, with no sunken areas or obvious infections/infestations, are most important. An otherwise healthy animal that is missing an arm or two need not be disqualified from purchase.
Acanthaster (Crown-of-Thorns); ****; C - photos courtesy of wikimedia.org
Size: these beautiful animals can hit 15'' across. As such, needs a large tank, nothing under 90-120 or so gallons, preferably long, wide and shallow. Should have some live rock, but the star may strip it clean. Good for tanks without corals or slow moving inverts.
This is the star that has, freed of predatory pressure and had their larvae overfed by man, "destroyed our reefs"; by all means buy one if you want. Is very pretty, but handle with great care. Do not ever touch the spines.
Feeding: prefers hard corals, especially SPS, but will also accept smaller meaty foods and algae.
Compatibility: it is unlikely that an aquarist will have anything that preys on this star. Harlequin shrimp, Triton Trumpets, and Napoleon Wrasse are all predators in the wild. (4)
Asterina, ***** photo courtesy of pirx.com
Size: Very tiny, typically as hitchhikers. I saw one in my tank that was perhaps 3/4'' across, see-through with red spots. Often breeds prolifically.
Feeding: usually eats algae, sometimes corals. Will do well with plenty of rock.
Compatibility: often cultured as food for harlequin shrimp. Will likely be chomped by fish with crushing or sharp jaws.
A note on other Asteroids:
Could be treated as with Fromia if small, as Linckia or Archaster if large. Do make sure the one you are buying is not a predator.
Ophiuroidea
Brittle Stars, ***** - photo courtesy of seasky.org
photo courtesy of wikimedia.org
photo courtesy of King County Natural Resources and Parks
These animals are among the best scavengers for a reef tank. They do not bother living things generally, but green brittle stars may learn to capture live fish. In direct contrast to asteroid stars, brittle stars can move very quickly, throwing themselves about with their long arms. May spend time hidden.
Size: highly variable, many come as hitchhikers on live rock, others can be quite large. They can easily be kept in nano-tanks, and to be kept in groups the larger specimens should be provided with ten gallons an individual. Minimum tank size, in my opinion, is ten gallons, and the smallest ones can be kept in tanks as small as a gallon.
Feeding: simplicity in itself, brittle stars accept leftover fish foods without hassle. It may be a good idea to directly feed the largest ones with krill or squid pieces.
Compatibility: Can be attacked by large wrasses, puffers and benthic triggers. If the star has a good shelter, the chances of predation are reduced. Arms will regrow if broken.
Sources
-http
/www.wetwebmedia.com/seastars.htm
-http/en.wikipedia.org/wiki/Asteroidea
-Marine Fish and Reef USA, "STARSTRUCK!" by Jeff Kurtz, pages 100 and 101
-http/www.liveaquaria.com/product/scateg.cfm?pCatId=528
Written by Lynden B.
I give permission for anyone to copy this article in whole or part for any reason, on the condition that the sources are credited.
I will also include a simple 'rating' for each star. A '*****' indicates a very hardy and easy to feed star, whereas a '*' indicates that few people have had any success keeping them for periods over a few months. Also a 'C' indicates that the star feeds on visible ornamental fauna and is thus "un-reef-safe".
All starfish (and all echinoderms for that matter) can go a long time without food. I suspect that most aquarium "for no reason" deaths result from lack of food, leading to the star slowing to a stop over a period over a few months, followed swiftly by death.
First a general description.
All echinoderms follow a pattern of penta-symmetry (five sides that are all the same). They move via a system of tube feet: the thousands of tiny sticky pads under the animal. Their vascular system is hydraulic. There is no circulatory system and all gas exchange is accomplished by simple diffusion.
Starfishes typically extrude their stomachs to envelope food and digest it externally, whereas urchins have five strong teeth that are self-sharpening and used to grind apart foods.
A note often brought up is acclimation times. I cannot speak with any experience on this subject as my brittle and choco chip (got them at the same time) both fell over in the tank after fifteen minutes and they lived until the tank crashed (due to outside causes) several months later. It would be safest to drip acclimate the animal over a period of an hour. Use a bucket, and place the star on a piece of live rock so that it doesn't need to be detached from anything when it is ready to be placed in the tank.
Selecting a healthy specimen is important. An active animal, with no obvious infections/infestations, or lesions on the skin, is good. A missing arm need not disqualify a specimen from purchase, unless the injury site appears to be necrotic. If the store will do so, ask them to place the animal on it's back, and see if it's able to right itself; specimens that cannot may lack the stamina to be taken to a new environment.
On a similar note keep water quality as high as possible. That means biweekly water changes of fair proportions (25% in my case), no ammonia/nitrite, and as little nitrate as possible. While it is true that many stars can be hardy, it is best not to take chances, especially since changing water isn't much work.
Lastly, though I consider this article a good source (though decidedly short), it is always best to research from many different sources. Do read the links provided if you are looking at purchasing any starfish.
Species profiles (Asteroidea)
Protoreaster (such as chocloate chip, and red general); *****, C
Red General, P. lincki - photo courtesy of wikimedia.org
Chocolate chip, P. nodosus - photo courtesy of wikimedia.org
Size: Chocolate chip stars can occasionally hit 8'' if given time and adequate food, and red generals can grow even larger. These stars do not need as much room as similar sized microfauna eating stars do, but I would suggest nothing short of a 75 gallon for a full grown red general, and at least 55 gallons for a full grown choco chip. With that said, they can be kept in slightly smaller quarters (though not ideal) and baby sized ones can be kept in tanks appropriate to their size, even nano tanks for a time.
Feeding: these stars are voracious omnivores. They will eat anything they can catch, even fish from time to time. It would be wise, therefore, to include them in fish-only tanks with large, wary fish such as angels or Anthias.
Feeding should consist of offering 'bite' sized pieces every other day or so. Suitable foods are silversides, shrimp, squid, clams, and anything other sea-faring food fit for human consumption. Good ways to offer the food is to shove it into a rock crevice; put it in the same place every time, and the star will learn to go to that place when hungry. Nori can also be offered.
Compatibility: large, nippy fish, such as Thalassoma, Coris, and Novaculichthys wrasses, plus the largest of benthic triggers and puffers, are all capable of killing a Protoreaster. Avoid housing the two together unless both are very well fed and the fish was purchased at a young age. Apparently very few predators will eat these stars, however. (1)
Archaster, Astropecten, Sand sifting star; ** - photo courtesy of liveaquaria.com
Size: these guys can reach a foot in diameter, though they will probably remain smaller. They need a wide, shallow (as in vertically) tank of preferably a few hundred gallons. Need large amounts of sand and little rock, and can denude tanks of microfauna when large.
Feeding: the hardest part. Will eat anything alive in the sand bed, and they tend to be hyperefficient, clearing even seemingly large tanks of food in a few months. It remains to be said if they could eat food placed in the sand bed, but perhaps it would be a good idea to overfeed the tank on a regular basis to breed prodigious amounts of microfauna. Of course keep up with the water changes.
These animals are hardy for the most part, the only real concern is feeding. Highly compatible with most other livestock, but large wrasses and large benthic tetraodonts are capable of digging up and killing these stars. Shouldn't be too much of a problem.
Fromia (such as peach star, Indian star, marble star); *** - photo courtesy of liveaquaria.com
Size: Fromia are among the smallest of ornamental starfish and as such are much easier to provide for than most. According to liveaquaria, the pictured species only reaches 3'' in diameter. (2) Should have a tank of at least 40-50 gallons with as much live rock as is aesthetically acceptable (for one adult specimen).
Feeding: eats tiny creatures and algae. It will help the star if one were to allow "pest" algaes to grow, as these will harbour an enormous amount of 'pods and other microfauna. Still, it is best not to have any other microfauna eaters in the tank and these would include mandarins, fairy wrasses, pipefish, etc. Though if one attached a refugium to the tank, it would probably work.
Compatibility: large puffers, benthic triggers, and large wrasses may try to eat this star. The star itself typically leaves ornamental animals alone.
True Linckia (such as the blue star); ** - photo courtesy of wikimedia.org
Size: these stars can become quite massive, sometimes (but very rarely) reaching 15'' in diameter. A medium to large specimen, about 5-6'' in diameter, will need a large tank with a huge amount of live rock. A full-grown specimen (13-15'') should be provided with nothing short of a one hundred gallon tank, with as much rock is as aesthetically acceptable. I have heard the minimum for these species varying between seventy five to several hundred gallons.
Feeding: as above must be given a large amount of live rock. The true feeding needs of this starfish are poorly understood, but it would appear they are largely bacteria eaters, undoubtedly with some algae and microfauna included. Therefore the very best way to keep them fed is with live rock and slight overfeeding of the aquarium, but feeding can apparently be supplemented, if one uses very tiny foods (such as mysis fragments or brine shrimp) and makes absolutely sure that the star grasps it. I suspect that this alone will not keep them well fed forever, as one point being they are often unreachable in the reef tank. (5, contributed by tat2life)
Linckia are often damaged in collection, and it would appear that up to ninety-five percent of them can be damaged beyond recovery. (3) It is very important one selects a healthy specimen; one that is active and rigid, with no sunken areas or obvious infections/infestations, are most important. An otherwise healthy animal that is missing an arm or two need not be disqualified from purchase.
Acanthaster (Crown-of-Thorns); ****; C - photos courtesy of wikimedia.org
Size: these beautiful animals can hit 15'' across. As such, needs a large tank, nothing under 90-120 or so gallons, preferably long, wide and shallow. Should have some live rock, but the star may strip it clean. Good for tanks without corals or slow moving inverts.
This is the star that has, freed of predatory pressure and had their larvae overfed by man, "destroyed our reefs"; by all means buy one if you want. Is very pretty, but handle with great care. Do not ever touch the spines.
Feeding: prefers hard corals, especially SPS, but will also accept smaller meaty foods and algae.
Compatibility: it is unlikely that an aquarist will have anything that preys on this star. Harlequin shrimp, Triton Trumpets, and Napoleon Wrasse are all predators in the wild. (4)
Asterina, ***** photo courtesy of pirx.com
Size: Very tiny, typically as hitchhikers. I saw one in my tank that was perhaps 3/4'' across, see-through with red spots. Often breeds prolifically.
Feeding: usually eats algae, sometimes corals. Will do well with plenty of rock.
Compatibility: often cultured as food for harlequin shrimp. Will likely be chomped by fish with crushing or sharp jaws.
A note on other Asteroids:
Could be treated as with Fromia if small, as Linckia or Archaster if large. Do make sure the one you are buying is not a predator.
Ophiuroidea
Brittle Stars, ***** - photo courtesy of seasky.org
photo courtesy of wikimedia.org
photo courtesy of King County Natural Resources and Parks
These animals are among the best scavengers for a reef tank. They do not bother living things generally, but green brittle stars may learn to capture live fish. In direct contrast to asteroid stars, brittle stars can move very quickly, throwing themselves about with their long arms. May spend time hidden.
Size: highly variable, many come as hitchhikers on live rock, others can be quite large. They can easily be kept in nano-tanks, and to be kept in groups the larger specimens should be provided with ten gallons an individual. Minimum tank size, in my opinion, is ten gallons, and the smallest ones can be kept in tanks as small as a gallon.
Feeding: simplicity in itself, brittle stars accept leftover fish foods without hassle. It may be a good idea to directly feed the largest ones with krill or squid pieces.
Compatibility: Can be attacked by large wrasses, puffers and benthic triggers. If the star has a good shelter, the chances of predation are reduced. Arms will regrow if broken.
Sources
-http
/www.wetwebmedia.com/seastars.htm-http
/en.wikipedia.org/wiki/Asteroidea -Marine Fish and Reef USA, "STARSTRUCK!" by Jeff Kurtz, pages 100 and 101
-http
/www.liveaquaria.com/product/scateg.cfm?pCatId=528Written by Lynden B.
I give permission for anyone to copy this article in whole or part for any reason, on the condition that the sources are credited.
