OK I have a fairly easy solution to do. These are you options
#1 Buy a loach or snail eater of some sort, you cannot do this in your tiny fish tank because these fish get big (if you get a bigger tank in the future this could work though)
#2 Buy a snail killer from the store (this may harm or even kill your current fish though)
#3 Stick a piece of lettuce on the bottom of the tank, wait overnight, then in the morning take the lettuce out with all the little snails on it and dispose of it.
#4 Go all out barbaric and remove each snail by hand and whack em with a hammer
Good Luck!
