Snails can be a welcome addition to the freshwater tropical fish aquarium, or they can quickly overrun the tank and become a huge pest. If you wish to add these helpful invertebrates to your fish tank to help keep it clean, make sure you pick the right ones.
The mystery snail, which is sometimes called the apple snail, is one of the most popular snails to add to an aquarium. Because they lay their eggs out of the water, there is little chance of this snail overtaking aquariums through quick reproduction. They are, however, excellent scavengers, eating excess fish food and some algae. The shells on these invertebrates are quite colorful, so they add beauty as well as function to the tank. They can grow quite large, up to six inches in diameter if cared for properly.
Like the mystery snail, the ramshorn snail is a larger snail that eats excess food and some algae. They tend to have dark shells and do a great job of cleaning algae off of the glass and most aquarium decorations. These snails are perfect for tanks kept in sunlight, as these aquariums tend to have a high problem with algae that is difficult to control with typical aquarium supplies. These snails do breed, but they do so slowly, and the resulting offspring can easily be removed from the fish tank if the owner so desires.
If you have a large tank, you may like the melantho snail. These snails have a horn-shaped shell, rather than the traditional spiral shell. They start out quite small and breed rapidly. In a small fish tank, they will quickly take over, so you will have to keep the population trimmed if you wish to keep these snails. However, they are excellent scavengers and do a great job of at keeping algae at bay. Watch for the most activity from these invertebrates at night.