Another hole in this region is linked to the intestines, and is used to expel wastes. Land snails are hermaphroditic, that is, each snail has both male and female parts. They still must mate to reproduce, however. A hole near the head is the genital orifice where the snail mates and also where it lays its eggs. Aquatic snails have both hermaphroditic and heterosexual reproduction.
Most snails lay eggs.
Any damage they do cause will be compensated for by fast plant growth. Malaysian trumpet snail The Malaysian snail, Melanoides tubercularia, is an interesting creature in that it lives in the substrate during the day and only comes out at night. Its shell is a perfect cone shape and gets to about 2 cm long. It is a livebearing snail and reproduces quite readily. It is considered beneficial to a plant tank and doesn't seen to harm plants, even in large populations.