I have a 10 gallon fish tank with 3 small goldfish in it. today I noticed alge growing on some of the rocks and my decoration. would it be ok for me to buy a snail to eat the alge? I know that everyone says that a goldfish can't be in a tank that small, but my friend had 3 goldfish, one alge eating fish, and like 10 small snails in a 10 gallon tank and they lived fore like 9 years! Thanks!!