Starfish being eaten?

[Siscim23]

I have a few sand sifters and one of them I noticed was missing a leg, all the way to the mouth. Then I saw on top of another leg there was a chuck missing (about 1 cm long). It was still moving around the tank fine so I assumed it was going to be okay. Today I noticed a second leg almost completely gone, only about 1/2" left and it was chewed up some.

Fish/inverts include:
damsels, Scopus Tang, skunk cleaner shrimp, 2 clowns, 1 green chromis, turbo snails, hermit crabs, horseshoe crab, and I had a blue knuckle hermit crab but I haven't seen it in about a month.

I see some of the starfish going through a hammer torch coral I have, but I don't think this could harm them. and I saw a small piece of one of the starfish legs near a bubble coral. Could the corals sting starfish?


Any ideas as to what could be munching on the starfish? It's only one of them that I see damage, the other 2 are fine. I seem to remember someone mentioned starfish eat themselves if the do not find anything to eat? Could this be the case as well (if that is even true)?

 

[greenbean36191]

Yep, they're starving to death. Nothing is eating them. They feed on sandbed infauna and are unsuitable for captivity, especially small tanks. Even a single one without any competition would eat itself out of house and home in a few months in a 29. Adding direct competitors such as a horseshoe crab (also unsuitable for captivity for the same reason) and two other stars is a sure death sentence.

 

[Siscim23]

Okay thanks. I guess I'll take the other two back to the LFS before they start to do the same.