Tadpole Snails (Physella) are prolific eaters and breeders. That's why they are called pest snails. They are great to feed to your freshwater puffer fish and other shell breaking freshwater fish.
Feeding Puffers live snails keeps them busy and their beaks in shape.
Tadpole snails clean up uneaten fish food and recycle fish waste into plant friendly ground.
This is great to keep your gravel clear and you are likely to notice a slight boost in plant growth.
But due to their breeding habits the snails need to be weeded out often or fed to a snail crunching fish.