There's a lot of things that might have happened... It could have just been a bad shipment or they were sick before you got them Dx; there's no real way of knowing... things like internal parasites are hard to identify )':
but a good place to start is by check all your water parameters. If something is a off, that might be the case, or not...
I dunno O_o; watch them closely and look at their behavior. If they're possibly sick, maybe look for symptoms?
Of course it might've been stress also, but you got them earlier this month didn't you? When did you put them in all together?
Last edited by BakaMandy; 08-18-2009 at 10:11 PM.