Swollen Loach

[CatLover]

I have a 6 inch dojo loach in my tank. I noticed today that he is extremely swollen from the back of his head all the way to his vent. The last inch of his tail is the only part of his body that isn't huge. He is round, and fat, and looks like small snake that just ate a rat. I didn't think he would have eaten another fish, seeing as his mouth isn't designed for that, but I did a quick inventory of thetank, and everyone seems to be counted for.
What in the world is this? All params are good, and he isn't overfed.

 

[Aprilia997]

It sounds like dropsy which is fatal in most cases. It is a viral disease and very hard to treat but is not very contagious. Your other fish should be fine but keep a close eye on them.

 

[Lateral Line]

Botias have a habit of stuffing themselves to the point of exploding. I think the likely cause is he's found something he likes and has eaten a load of it. Snails maybe. Before suggesting any kind of disease, I'd not feed for a couple of days and see if he "recovers". Of course, if his secret food supply is already in the tank, that won't help.