Lost 5 XL Chromis in QT

[BWine]

I recently lost 5 XL chromis in my QT. I'm not sure what happened. I woke up Saturday morning and found 1 dead. I just thought that the other 4 killed it. By Saturday night, 2 more were dead. I tested the water for ammonia and nitrite but both tests were zero. By sunday morning, the last 2 were dead.:confused:

I'm not sure what killed them. They were in my QT for almost 3 weeks and they've been eating since day 1. There wasn't any sign of ich or scars. So I'm guessing that they had some kind of internal infection/parasite. They were purchased from LiveAquaria.

Anyway, I plan on going to the LFS this weekend to get some other kind of fish, not sure what though. Should I do a 100% water change on the QT? I also have a bio-wheel filter on the QT, should I throw the bio-wheels out?

Thanks!
Mike

[oli5]

yes, whenever you take out a fish from the QT and put a new one in, you always have to start with new water. For the chromis, I don't know what to say about that because that's really strange. Anyway, good luck.

[team2jndd]

dont get any new fish until you find out what killed the others. If they had some sort of disease or internal parasite they shouldnt have been eating regularly. Fish dont just die overnight from disease without any signs of distress. I would test for other things before buying anything else.

[BWine]

Yeah, i thought that it was really strange too. I'm not sure what happened to them. Should I throw out the bio-wheel filters?