PlanetCatfish.com

I have a moderate infestation of pond snails in my 20 gal. planted cory tank. I try to keep the snails in check by killing them manually when I see them; crushing them against the glass. Within a few seconds my cory cats will gobble up the remains. My question is, can any harm come to the fish this way? My main worry is that they will ingest shell fragments, tho I admit I'm also not sure of any toxins the snails may carry that would be bad for my catfish. My corys are aeneus and trilineatus. Does anyone have any thoughts on this?

I don't think the shells are any danger - the fish will frequently pick up substrate and separate edible bits from non-edible, spitting the non-edible back out.

Common snails aren't toxic to fish, so unless you have some obscure species, I wouldn't worry about that either.

The worry I would have is if there's any illness in the snails that transfer to the fish - which may happen. On the other hand, if they are already in the same tank, you're not really changing anything, since the pathogen would already be in the tnak anyways...

--
Mats