Freshwater algae eaters include a variety of shrimps, snails, and algae eating fish. The best freshwater algae eater for a particular tank depends on the type of freshwater habitat, the current aquatic residents and the aquarium owner’s taste.
Shrimp can be a great algae eating option in a freshwater aquarium. According to Home Aquaria, the Amano shrimp is one of the best algae eaters and will even scavenge decaying plant matter and leftover food. Other shrimp varieties include the red-colored Cherry shrimp and the ghost shrimp, which is often sold as feeder shrimp. Owners should keep in mind that shrimp are more delicate than snails or fish and therefore more vulnerable to being eaten by predators sharing their environment. For this reason, shrimp are not suitable for ponds where large fish would quickly make a snack of them or aquariums with aggressive fish, such as cichlids.
Snails are an excellent and inexpensive algae eater. Pond snails are very tolerant of temperature changes and are effective algae eaters for the pond environment. In the home aquarium, the Nerite snail is a common favorite. It eats most types of algae but not live plants, sports a colorful shell and is only an inch when fully grown. In contrast, Apple snails, also called mystery snails, can grow up to the size of a grapefruit. Ramshorn snails are another good small snail option, measuring less than an inch.
Aquarium owners should be aware that both Ramshorn and Apple snails have been known to eat aquarium plants if they get hungry enough. Even though snails have more armor than shrimp, hungry cichlids will still consider them food if there are no better options. Good snail care includes maintaining a slightly basic pH, which should be just over 7, and adding a calcium supplement for shell growth.
Fish should not be overlooked as an algae eating option. Siamese and Chinese algae eaters are active swimmers that thrive in the pond environment and in the aquarium, as do most varieties of plecos. When dealing with algae in an aquarium with aggressive tank mates, adding a pleco is often the best option. This well-protected algae eater will also clean up plant matter, and only the boldest, or hungriest, of aggressive fish will find its spiny armor worth the trouble.