Sea cucumber acting odd

Engloid · Apr 9, 2011

I have a few in my tank, and one is standing vertically. Only about an inch of his body is on a rock, but about 4" is staning vertically. There's a point on the top of his head that is releasing a milky substance. In the water, it looks like smoke coming out, but of course it's not bubbles.

Is this a mating thing, releasing sperm or something? I just want to make sure this isn't something bad that he's doing an I need to get it out of the tank.

DevinWolfe · Apr 9, 2011

Mine did this in his QT tank w/ a Damsel, the Damsel died within hours. Based on descriptions I had read I believed he was eviscerating. These animals will expel toxins in their system when they come under stress or feel threatened. They recover, but can sometimes do major harm to the other inhabitants.

Poisonous Animals: Sea cucumbers (Holothurians); Star fish

WetWebMedia - SeaCukes

Many argue that it is harmless; I believe differently. I recommend doing research to formulate your own opinion rather than taking mine.

Edit: P.S. I do NOT recommend moving him to a QT, it actually turns out that a QT can sometimes CAUSE enough stress to cucumbers due to a lack of maturity.

Engloid · Apr 9, 2011

I'll read up on the links you sent, but my inclination is that it's some sort of breeding thing, rather than something caused by stress. Nothing like internal organs came out, and it was from a small hole on his head, not on his "backside."

This guy's been in here for a couple months, and seems to do just fine. Nobody picks on him. He tends to not like light, so he comes out more at night. Today though, he was right out in the open and standing straight up while expelling the white liquid. It just seems if he was stressed he wouldn't be out in the open, but hiding.

I'm gonna keep reading and check the links. Thanks!

Raven1645 · Apr 9, 2011

I've read they release a grey cloud upon death, possibly removing all oxygen and resulting in a tank crash.
Yours most certainly isn't dead but the cloud sounds similiar, so I would keep an eye on your other fishes and maybe refresh more water than usual.

Engloid · Apr 9, 2011

Raven1645 said:
I've read they release a grey cloud upon death, possibly removing all oxygen and resulting in a tank crash.
Yours most certainly isn't dead but the cloud sounds similiar, so I should keep an eye on your other fishes and maybe refresh more water than usual.

This guy's already back to grazing, so I don't think it's death either.

Devin, eviscerating...from what I have read, is a process in which they expel their internal organs...as a defense to being attacked. Similar to a lizard's tail that comes off easy to save the rest of the body from a predator. The sea cucumber can quickly grow back the organs they expel.