Snails make a great addition to any cleanup crew for your saltwater aquarium, but not all snails eat algae. When shopping for an algae-eating snail, look for snail species that are herbivores or omnivores. You may find that some carnivorous snails -- such as the bumble bee snail -- are sold as good algae munchers, but they won't actually clean up any algae in your aquarium. Four of the best saltwater snails for combating algae include turbo, astrea, turban, and nerite snails.
Turbo snails are native to the Gulf of California off the coast of Mexico. There are about 60 species of turbo snails that can be considered aggressive cleaners and will scour your entire saltwater aquarium, top to bottom, eating nuisance algae. At the same time, these snails will bulldoze loose rocks and may rearrange your aquarium. If they fall over and onto their backs, they may die if they aren't righted. Make sure to have rubble in the sand bed so they can right themselves, and avoid keeping turbo snails with aggressive fish that may intentionally flip them over. Turbo snails are great for battling green hair algae.
Astraea snails are native to the Caribbean; they are a smaller snail, only reaching about one inch once fully matured. Like turbo snails, they'll scour the entire aquarium and will bulldoze lose rocks and decor. Keep rubble in the sand bed so that if the snails fall upside-down, they can right themselves. Astrea snails will keep your aquarium clean of algae, especially cyanobacteria and green and brown film algae, but they tend to leave green hair algae behind. Astrea snails are peaceful; they will not disturb other creatures, decor or landscaping in your aquarium. Consider adding one snail per every six or seven gallons of water.
Turban snails (also known as trochus snails) are native to the Indo-Pacific area. They will scour all decor, the aquarium bed and the glass. Turban snails are slow-moving and will eat a wide range of algae and are ideal for aquariums with green algae, hair algae, filamentous algae, slime algae, cyanobacteria and diatoms. These snails do not leave anything behind, making them a perfect choice for your saltwater aquarium. Turban snails are great for reef tanks and aquariums with a lot of live rock because they are less likely to stress out corals. Many hobbyist will keep as many as one snail per every three gallons of water.
Nerite snails are native to the Caribbean and the Pacific Ocean. They spend most of their time on the rocks and glass of your aquarium. Nerite snails are great against cyanobacteria and green algae; they're great window cleaners, removing algae film on the glass walls. These snails typically do not disturb landscaping and can right themselves if they fall over. Nerite snails tend to hang out at the top of the aquarium and may try to escape, so make sure to keep a lid on your tank. These snails are probably one of the best snails to keep in your saltwater tank -- not only are they pretty hardy, but they're thorough when it comes to cleaning your tank. Many keepers add one nerite snail for every gallon of water.