Exactly my thoughts when I found the body... The other two look better - these two seemed a bit 'off', since they came. One of them laid on the bottom of the tank periodically, until I came over and then it swam away as if nothing was going on. Then the other kept trying to squeeze behind the suction cup clamp for the powerhead. I couldn't find it for the longest time, and then I happened to see it popping out of there. Then it kept going back and getting behind there again.