Bumble bees not fully trustworthy.
They clean away detritus, including uneaten meaty foods and decomposing organisms. This tiny member of the Buccinidae family also burrows into your sand bed, consumes sand-dwelling worms, and helps aerate your substrate.
BUT . . . . . The Bumble Bee Snail is a carnivore. If there is insufficient food, the Bumble Bee Snail may feed on other snails in your aquarium or indiscriminately consume polychaetes whether beneficial or the more troublesome bristleworm. In well-established systems, most Bumble Bee Snails do not require supplemental feeding. However, if sufficient food sources are unavailable, supplement their diet with offerings of meaty foods, including finely chopped brine or mysis shrimp and frozen meaty foods.