Could be that the shells are too hard for your puffers at this size? I know ramshorn are a common snail people like to feed their puffers due to the fact they are such prolific breeders, and there shells aren't too hard (like MTS, which i've heard stories of peoples puffers chipping their teeth on)...It doesn't eat the nerite snails. Hopefully it will eat other snails; still need to get some. It loves bloodworms. Should be crayfish season soon and our office pond gets tons of tiny ones; can't wait to throw some in the tank.
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