Molly is listless and not eating...?

Question

I've had my black molly for about two months now and up until a few days ago, he ( she?) had a huge appetite and was very active in the tank. Now, he swims around listlessly, if at all, and does not eat. He hovers in one spot a lot (like the glass cats) and does not seem to recognize food like he used to. He'll swim at the top when it's feeding time, but won't eat anything. He used to be a real go-getter about food, but now it looks like he's at the top of the water when there's food only by chance. Also, his fins don't look as well-formed as they used to. What's wrong with him? Thanks!

Tankmates, in a 10-gallon tank:
- male betta (not aggressive at all, has never attacked the molly)
- long-finned danio (he and the molly used to chase each other around until the molly became despondent)
- african dwarf frog
- glass catfish (2)
- Chinese algae eater

The other fish in the tank are fine. Could the molly be eating the eggs from my snails and getting sick off them? I've noticed I'll see snail eggs one day, but not be able to find them a day or so later.

Answer 1

Could be a disease. If it is a she, she might have egg-binding, which would cause the abdomen to appear swollen. A fungal disease would make the fins look whitish and ragged--if they're not, someone is biting them. It could also be difficulty digesting the last meal. I always look at what is going on with everyone else in the tank to decide on treatment for a disease, because remedies in and of themselves have side effects.