Another "ID please" thread

[quil]

What on earth is this, and is it safe in a reef tank?

 

[skeletoncowboy]

lol that thing is crazy looking. my best guess would be a nudibranch...but i'm most likely wrong.

 

[quil]

Yeah, last time I saw something strange in the tank, it was a nudi, and they ended up wiping out a colony of zoos. Trying to avoid that situation if possible this time...

 

[royal gang]

sand sifting cucumber? or some other type of cucumber?

 

[texasmetal]

Definitely a sea cucumber of sorts. Most likely a filter feeder or sand-sifter.

 

[ric maniac]

i would leave him in. he looks like a sifter or a filter feeder.

 

[ophiura]

I would say most likely a filter feeder but you will need to see the feeding tentacles to be sure. Definitely appears to be a cuke though