Algae eaters keep water healthy. There are different varieties of algae eaters and different types of algae. Algae are a daily issue in freshwater. Conditions like lack of sun, poor quality water and too many plants create algae in freshwater. Freshwater creatures like shrimp, otocinclus and snails eat algae. Not all algae eaters are compatible with other fish. Scavenging for food can make algae eaters aggressive.
Freshwater shrimp eat algae from tropical aquariums. Shrimp lay eggs after breeding in the tank, producing numerous algae eaters that can take over your aquarium. Shrimp thrive in tanks with plants. Brackish water is a perfect breeding ground for shrimp. It is important to remove any shrimp eggs after spawning to keep a healthy aquarium. Shrimp need algae to maintain their health, but green vegetables can supplement their diet.
Freshwater shrimp are scavengers of algae. Two kinds of freshwater shrimp are suitable for aquarium use: P. kadiakensis and K. paludosus. These shrimp live in flood plains throughout the Mississippi River area and as far west as San Antonio, Texas. The freshwater shrimp called genera Macrobrachium eats algae, but grows too big to live in an aquarium. Shrimp are not aggressive, but when foraging for food any fish not finding enough to eat will become aggressive as a natural survival instinct.
The otocinclus or "oto" thrives on eating hard algae growing on plants, rocks in freshwater. Hard algae is not green. The otocinclus is no larger than 40 mm in length, allowing it to seek algae in small crevices. The otos can have their diet supplemented with plant food when there are not enough algae to keep them fed. The otos can also eat raw green vegetables like zucchini and lettuce.
There are two types of algae eating snails, the Malaysian trumpet snail and the zebra snail. The Malaysian trumpet snail is nocturnal and scavenges for algae on dead plants. This snail also eats leftover food from other fish in freshwater. The zebra snail is also an algae eater that breeds like shrimp in brackish water. The zebra snail can overtake a pond, lake, river and aquarium making it imperative to remove babies as soon as possible.