IOTM: Seastars Part II

ophiura

Active Member
PART II – Beasts of Burden and the Reef Ruiners
This is a continuation of the Invert of the Month series on seastars. General information was provided in Part I, which is a good place to start.
https://www.saltwaterfish.com/vb/showthread.php?t=180772
The water parameters required for these stars should be considered the same. All echinoderms need to have stable specific gravity, around 1.025-1.026. Most also need a long slow acclimation, especially if your tank is much different from the LFS. Additionally, be sure to check for disintegration of the arm tips or whitish patches before purchase. All are prone to suffer from acclimation shock, which may set in up to a month after introduction.
The beast of burden:

Archaster typicus (Sand Sifter Star)
Similar in appearance but not commonly in the hobby:
Luidia sp
Astropecten sp
A popular type of star in the hobby due to an unfortunate misconception – that it eats algae and detritus. While some of these stars may take to spot feeding and scavenging, its actual diet seems to consist of microfauna found in the sand. This includes worms, crustaceans and other beneficial creatures in a sand bed. These stars should not be put in tanks that use a functional deep sand bed as they consume the critters that keep the sand bed healthy, as well as disturb the stratification of the sand bed. The drawback is that in tanks not using a sand bed, and a very large one at that, these stars may quickly starve to death unless they do take to spot feeding. For this reason, it is a no win situation. I suggest trying a variety of foods and putting it in their path, and hoping.
The simple fact is, however, that most WILL DIE in captivity within a year in all but extremely large tanks with very large surface areas of sand (meaning 100+ gallon tank with minimal live rock), after a long slow starvation. The death is characteristic, and involves the slow disintegration of the arms. Often it will turn up with an entire arm missing, and then another chunk, and another. Hermits and other scavengers may also go after the star at this time, and many owners may be led to believe that the hermits KILLED the star, when in reality they were taking advantage of a dying animal – something we buy them to do.
I do not recommend keeping these stars at all.
As an aside, a couple of stars turn up from the Caribbean and Gulf of Mexico that may appear similar, so I've included them here. These are members of Luidia and Astropecten
. They look quite like Archaster
but are not close relatives. Behaviorally they may be similar, and will burrow into sand. But be forwarned if you are wandering around in Florida and want to bring one home. These can be highly
predatory. How about a story about one?
Here is a story from the Echinoderm Newsletter (on the Smithsonian website).
http://www.nmnh.si.edu/iz/echinoderm/1999/luidia.htm
 

ophiura

Active Member
Reef ruiners:
Protoreaster nodosus (chocolate chip star)
Protoreaster Linckii (Red African, Red General star)
Oreaster reticulatus
(Bahama star)
Culcita novaeguineae
(Cushion star)
Several types of “opportunistic” predatory stars can be found in the hobby. The most common are the chocolate chip star, and the red African or general stars. Though not reef safe, these stars are popular as they are relatively hardy, and can be spot fed. However, they should never be considered reef safe. They can and will catch and eat slow moving or sessile invertebrates including snails, corals, sponges, clams, scallops and the like. There have been some reports of them even catching small fish. Whether true or not, they will certainly be attracted to dead fish.
I strongly recommend that these stars be spot fed. That includes a variety of foods, and diversity is critical. Try algae sheets and wafers, shrimp pellets, shrimp, squid, krill, silversides, mussels or clam. Put the food on the end of a skewer, and place it near the tip of the arm of the animal. It should move towards it if hungry. Often it will spend a lot of time in one area, slowly digesting its food outside the body, and sucking in the juices. These stars can evert their stomach, to digest food externally. Not all stars can do this, but it is pretty cool to see! The frequency of feeding depends on many factors, such as water quality, feeding of other inhabitants, etc.
I want to just mention that there are several reports that these stars “learn” to crawl up the glass and bend their arms back when they are hungry. I do not consider this a learned behavior in any way. It is entirely possible, and more likely, that they crawl to the surface of the water for other reasons (gas exchange, surface feeding, etc). Seastars do not have a brain, so they are unlikely in a few days to “learn” this behavior at a wholesaler (indeed if they are fed at all), then retain if while being transported to an LFS (where they are unlikely to be fed) and then to a home tank. This would be quite amazing if true. But I think overall it is just a nice sounding story to explain a weird behavior.
These stars are often kept in fish only systems so I will mention that many aggressive fish are predators of these and other stars. So avoid putting them in with triggerfish, large wrasses, and pufferfish. Watch large angelfish as well. Large hermits, crabs, and even other seastars can also be potential predators.
 

smoney

Active Member
hey Ophiura, I love these informational things you write. I had a question though, I want to get a starfish that is one that will be out(I already have a brisstle), And I was wondering if their is one that you would recommend for a 50 gallon reef tank, and soon a 10 gallon refuge attached? I would like something if color if possible?
 

ophiura

Active Member
How much LR, how old, and what are specific water parameters?
The trick is, none will be "out." Even Linckia stars will often not be visible for quite long stretches of time, feeding on stuff on the rocks in front, and behind

But I will let you know that your tank is quite small for one of these stars. IMO, the only one that stands a chance is Linckia multiflora (see "Seastars Part I"). This is a smaller star, reported to do moderately well in smaller tanks with nonethless a lot of LR. But it is still not an easy or sure thing
 

smoney

Active Member
I have a pretty decent amount of liverock, probably in the range of about 80lbs, plus a refugium. I was thinking of letting the refuge run for a while before I try a star fish. My tank is 14 months old, and I dont know my water parameters as of right now, I should do a test soon.
Do you have a pic of the Linckia multiflora?
 

sleeper

Member
OPhiura, I have a question for you:
I have heard legends of keeping stars in a fuge, propagating them by cutting (the old sailors' technique) and then feeding the "frags," if you will, to harlequins in a main tank.
Do you have any comment on that? Is it even possible? Is there a star that fits the following: 1) harlequins will eat it 2) reef safe 3) propagatable?
I suppose 2) is really optional if I'm keeping them in a fuge, but then I have to worry about them eating algae and pods.
Anyway, your thoughts are MUCHO appreciated! There's a pair of harlequins at my local and I'm really thinking hard about 'em. :help:
 

ophiura

Active Member
The only one's that fit 1,2 and 3 above would be the small hitch hiker Asterina stars, IMO. (well give them about 98% on the reef safe grade).
Chocolate chip stars are used for this, or can be, but they are not reef safe. However, this means they take to spot feeding, in general, and this is very important for an animal if you are cutting arms off. You have to ensure that you can get them the nutrition they need and thensome, so you will have to feed them well.
Otherwise, Linckia species stars do NOT eat algae and probably not "pods," by definition, which is why they tend to starve without a suitable amount of LR. So I don't think a refugium would be suitable for them long term - certainly not if you are going to chop off arms. And I don't recommend using Linckia stars for harlequin shrimp anyway. Enough die in this hobby as it is. If you choose to feed them, I would urge you to try freezing them and cutting off arms as needed to see if the shrimp will eat it, to make the most out of any single specimen.
So overall, keeping them is not the easiest matter. Definitely good to research

I am not sure how many people have actually tried the chocolate chip arm cutting technique. It would be interesting to know. In theory, it should work but I don't know people who actually DO it. But the Asterina stars should be easy to propagate...though being so small they would be eaten pretty rapidly. However, you could probably just slice them in half and have them regenerate pretty frequently.
 

sleeper

Member
Thanks, Ophiura, brilliant as always.
I'm upgrading to a 65 very soon and may go that route... we'll see.
BTW, are you a biologist/graduate student? That's what it seems like. If so, and if you do't mind, maybe you can email me at IanInDC@gmail.com and tell me how you got into it and at what point in life? I'm a young journalist and I like what I do but something about working with marine life has been hovering in the back of my mind for years.
 
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