snails for puffers
Florida puffers are naturally drawn to snails for food. Even snails that fall from the mangrove trees and float at the top of the tank. They recognize the shell shape that they are familiar with from the variety of species available to them from the ocean floor. If your puffer doesn't recognize the snail as food, try crushing it first to get the puffer interested. From there, the puffer will learn to try to suck the snail from the shell. I have had many puffers collected here in the Keys, and they come to the top of the tank immediately and suck the animal right from the shell, the same with sinking snails from the ocean.