How do aquarium snails reproduce and do you need to control them?

Aquarium snails don't all reproduce as easily as people think - it really depends on the species. Small snails like nerites or apple snails generally reproduce through sexual reproduction and need specific conditions, whereas some species like mystery snails are harder to breed in captivity. If you really want to control the population, it's mainly about keeping an eye on food (less food = fewer snails) and removing eggs if you spot them. Honestly, in most aquariums the population regulates itself without you having to do much of anything.