fry & snails

What kind of snails? If they're ramshorns or tulip (common pond snails), I'm surprised...the eggs are usually encased in a tough gelatinous mass that is very tough. Once newly hatched, all bets are off, as even ghost shrimp will make a meal of the newly hatched snails in my experience.

I don't see it as a problem if your guppy fry are still up and kicking.

v/r, N-A