I used to be able to feed snails to my turtle, but I no longer have a turtle, so that's out.
My favorite aquarium store suggested a yoyo loach to eat them, which sounded great until I got home and read up on them and discovered that A: even though they're small, the tank's still too small for them, B: they're schooling fish and I'd need to get at least 5 or 6 of them for them to be happy, C: they need a sand or very smooth substrate and I have pebbles, and D: they're boisterous enough that they'd be likely to upset my guppies. Also, it's possible they'd eat the fry, which would make me sad. So that looks like a big round 'no', and I am disappointed in my otherwise favorite aquarium store.
I'd rather not add chemicals to the tank that will have any effect on my fish, and it's hard to see how anything I add to the tank /wouldn't/ affect the fish. I don't mind hand-collecting snails to winnow down the population - and I don't mind that it won't get them all and I'll have to keep doing it - it's just a question of what I do with them afterwards. If I could feed them to something I would. But if I have to kill them to no good purpose, what's the best way? I can't dump them where they might get into the natural ecosystem of my part of the world, and I don't want to just resort to hitting them with rocks.
Advice? I know how to euthanize a fish - clove oil and then alcohol - but what about dozens and dozens of tiny snails? Also, is there anything I can do in maintaining the tank to make conditions such that they're less likely to breed like crazy?
Thanks for any thoughts.