I mean, that amount of snails would probably be ok, but overkill in my opinion. In my 56g I probably have 5 Mexican Turbos, 25 Nassarius, and another 10-15 assorted smaller snails. With that said, I also have a couple emerald crabs, 10 or so assorted hermits, a peppermint shrimp, and a few gobies that help with the sand bed sifting.