I agree Tmer also their population count will go down considerably via less breeding. trumpet snails are asexual, each snail is both male and female. so if the tank is overfed, the snail naturally breeds itself like crazy; less feed less snails

plus they are much stranger than olive nerite snails (which do not have any snails or offspring but only in brackish waters) when they graze over things...the trumpet snail looks like a vacuum cleaner when our of the shell whereas the olive nerite snail only partially comes out

steady supply of fish and invertebrate feeding will permit a steady rise in the level of trumpet offspring...in a way it's a way to make sure you do not overfeed, it has its own inner benefit in itself, you know? as if I am forced not to overfeed, because if I do, trumpet snails will have so many snails all over the place, that the tank will turn into a snail aquarium

nevertheless, thanks for the replies