Serpent Star Fish

[rtapia]

I have a tank that has been well established for a good while now. All parameters are great, all corals look good and are growing fast. My problem is that I have lost three fish since last week (1 long-nosed butterfly, 1 half-black angel and 1 small false percula clown). I can't find any clue as to what killed them, as my water is all testing good on pH, nitrate, nitrite, ammonia,etc. The only new thing added to the tank was a serpent star fish that was introduced about 3 days before the first death. This critter's head is about the size of a quarter and its tentacles are about 6 inches in length.
Any ideas?

[Twitterbait]

never had a star kill a fish. any weird noises in the night (i.e. mantis shrimp). or any indications of disease?

[wanareef]

If you don't see any bodies- then you have a great clean-up crew working. Kind of a hard way to tell


That brittle star is not big enough to do that or fast enough yet.

[Phishnoob]

I have a couple of serpent stars and they are peaceful...now my mean green killing machine brittle star is the bad boy at about seven inches across now.

Can you test your water and post everything for the pointyheads to ponder? Also temperature might be the issue here...as well as salinity. Three fish dying means a dramatic change happened that needs to be worked out.

[JennM]

Is it a serpent star (smooth legs) or a brittle star ("hairy"/bristly legs)? Green brittles are most notorious fish hunters, the others can but usually don't. Serpents generally don't ambush fish, but they could I suppose.

They don't have to be that big to do it either. They poise themselves like a tent with the body disc elevated off the tank floor, fish passes beneath them and they drop on them. Sea stars can push their stomach out of their body and around their prey so they can digest relatively huge prey, and as you said with cleanup crew there wouldn't be anything left.

Hard to say if it's the cleanup crew including the star, eating the ones that died by other causes, or if somebody's on the hunt.

Jenn

[wharyat]

As in size of your star is that length of one leg? or the total diameter? If he's 12" across I'd say that's your problem.

[Loverotties]

Mines close to that,maybe 11 7/8"

[chicagoman_35]

I've got a green brittle about 14" across, missing 4 fire fish, a mandarin, and a pearly jawfish... As soon as I catch him he will be impriosined in my sump!