In seawater aquariums we keep mainly shell snails. Although there are a variety of beautiful, colorful nudibranchs in the sea, but these are highly specific food specialists who would only starve to death in the aquarium. The snails in the marine aquarium are mainly kept, as they eat algae and so clean slices and stone structure.
Popular algae-eating snails are e.g. Tectus and Nerita. For the control of algae, 1 screw is normally used on 10 l tank contents as soon as green algae emerge after setting up the tank. Furthermore, there are sand-digging snails such as Cerithium and Nassarius, which circulate and clean the ground.