Excellent little fish that are normally very hardy. Very shy, so shouldn't be kept with aggresive fish or they will hide and not come out to eat. If kept in groups,in small tanks, one will usually start chasing the others, often until it kills them all. Provide coral rubble as suitable hiding place. - From Scott Michael's Marine Fishes.
From personal experience: Keep a lid on the aquarium. They can and will jump if spooked.
I had one jump out and my Springer Spaniel had a slimey treat before I realized what happened!
Thanks ppl, I picked him up last night, he looks great in the tank. Only prob is, I have a 3 stripe damsel, and a sebae clown that was put in at the same time. When it was just them, things were fine. Now I see the damsels agressive side coming out, guess he will go back to the lfs today. Is it just me, or has anyone noticed that when a firefish feels threatened, his mouth opens real wide? With that fin and large mouth its a pretty imposing sight. Thanks again, gotta go catch me a damsel. LOL
I had the same problem with a blue damsel. The little turd killed two other damsels while I was using them to cycle my tank. Then killed two more after that (the little $#@%$!). When I started to add new fish I tried a trick that I learned from the store where I bought it, took him out of the tank for a day/night and let the other fish get established then added him back in. It seemed to work or a least he is not picking on anybody else.