gaijin wrote in
:

I only have a few fish (now anyways) a couple of green chromis, a
maroon clown and a 6 line wrasse.

All appear healthy, happy and get along. However from time to time,
one of my fish just dissappear. They are eating fine and look fine,
and then overnight they dissappear.

Today I noticed that the 6 line wrasse has a huge chunk out of him.
How can I find out what is attacking my fish?


Do you have a fair amount of live rock, and the tank was set up in the last
12-18 months? Sounds like you have some kind of nocturnal ambush predator
as a hitch-hiker on your LR... maybe a mantis shrimp, or something similar.
Try hanging out with a flashlight after lights out, and see if you can
confirm it. There are traps for all kinds of nasties, if you can get a
positive ID.

Regards,
DaveZ