At one point or another many aquarists are surprised to find a colony of snails threatening to overrun their aquariums. Snails seemingly come out of nowhere and, in a matter of days or weeks, can reach such a population as to become a nuisance, even a hazard, to your aquarium. If you act quickly, things can be done to prevent the rapid reproduction of snails and you can remove them from your aquarium before they take over.
Where do Freshwater Snails Come From?
There are several ways that snails may enter your aquarium. While snails may enter an aquarium through gravel or substrate the most common way is via live plants. Snail eggs may easily be hidden among plant leaves and can be transported into an aquarium to hatch and multiply.
What do Snails Do?
A limited number of freshwater snails in an aquarium can actually be beneficial. Snails act as both algae eaters and scavengers - they help to control algae growth and feed on uneaten fish food and other debris. If allowed to multiply freely, however, snails in an aquarium can add to the biological load and they may even begin to destroy live plants.
How to Get Rid of Snails in an Aquarium
If you simply what to lessen the population of the freshwater snails in your tank you might try running hot water over a piece of lettuce for a few seconds before placing it in the aquarium at night. Because aquarium snails especially love to feed on decaying plant matter they will converge on the piece of wilted lettuce and you can remove both the lettuce and the snails attached to it in the morning.
If you want to know how to get rid of snails entirely, try introducing natural predators like loaches or pufferfish into your aquarium. These types of fish do not always get along well with other species but they can be very effective in helping to get rid of snails in an aquarium. You may also want to decrease the amount of food you feed your fish - limit their feeding to the amount they can eat within two to five minutes. Less uneaten food sinking to the bottom of the tank means less food for snails to scavenge. Chemical remedies like Copper Sulfate can also be effective but should only be used as a last resort because these treatments may also harm fish.
If you want to avoid having to deal with the nuisance of snails in your aquarium you can take a few simple steps to prevent them from ever entering your tank. Check live plants thoroughly for freshwater snails and snail eggs before putting them into your tank. As an added precaution you can even soak live plants in salty water for ten minutes - this will kill any aquarium snails, snail eggs, or other organisms living on the plant.
References:
"How to Get Rid of Small Snails," Aquarium Fish.net
"Pest Snails and Controlling Snail Population," First Tank Guide.net