I have common snails in my planted and community tanks.... I guess they hitched a ride in with the plants. They are not as big a deal in the community tank. I pick out a few every few weeks and throw them into my african cichlid tank... The cichlids love them.
I think most fish do, if they can fit them in thier mouth.
My planted tank only has a betta, and a cleaning crew. I notice I get a lot more snails from it. I think the tetra might be able to eat smaller ones. There is a definite differnce in snail population between my planted and community tanks.
And the snails never hit the bottom of my cichlid tank. No signs of snails in that tank.. I even thrown in the occasional plant, which also gets eaten by the cichlids.