Man down!

I got 3 blue/green chromis one week ago. One of them suddenly died tonight. I cant really tell them apart but one of them had been acting a little funny this weekend by hiding up near the top of the tank and in the rocks. I tested the water Saturday and everything was perfect. The three of them ate earlier and everything seemed fine. When i noticed it was dead I saw the other fish picking at the dead fish. Do you think they killed him? Should I get another to keep the number of chromis uneven?

 

possibly, however, look very closely at the fish- do they have any white spots on them?

BTW, I just noticed you are running fluval canisters- check your ammonia levels too.

 

No white spots.

 

it seems that green chromis only survive if there are 5+ from what ive experienced (may not be the case everytime however). I had 4 and every couple nights I would wake up to one missing until they eventually disappeared, but whenever speaking to someone with 5 or even 7+ they all live fine. weird?

 

BTW, I just noticed you are running fluval canisters- check your ammonia levels too.

 

They will pick each other off, regardless of numbers.
We saw a large group of them at the pet store, and one of them was being literally eaten alive by the others. I have no idea how it was still swimming as its entire backend was eaten down to the bone.
Everyone we've known that "successfully" kept a group told us they replaced the ones that got picked off to keep the number the same.

 

Chromis IME are VERY bad acclimaters, i have pristine water most of the time and when i bought some chromis a while ago, only 1 made it out of 3..I acclimated them by just floating, the next time i bought 2 more and dripped them for about 2 hours, they lasted..