If you ask any owner of a freshwater planted aquarium, they may tell you that snails are the most annoying thing in their tank. They normally come from plants either ordered online, traded with friends, or even bought at a local fish store. The reason why many people hate snails is because when given the right conditions, they can multiply rapidly and take over your tank without much effort. However, thinking about the benefits of these “pests” may allow you to let them occupy your tank in peace.
Aerate The Substrate
It doesn’t matter if you have standard gravel or specific planted aquarium substrate, your plants need both oxygen and carbon dioxide to live. Some pest snails (like the Malaysian Trumpet Snail pictured above) burrow into the substrate and create air pockets for these gases to hide out in. Creating the air pockets helps air out the substrate as well as sifting things like fish waste further into the substrate.
Overfeeding fish is one of the main causes of poor water quality. We all do it – by accident or on purpose – and some of the food will hit the substrate. Unless you have a team of catfish that will come out and instantly eat this food, no fish will want to eat it after it sits in the water for an hour or two – but snails will. My Malaysian Trumpet Snails eat leftover algae pellets, flake food, and even foods like bloodworms. I wouldn’t count on snails cleaning up the excess food, but it is nice if you accidentally feed too much.
Many freshwater snails have a diet made entirely of algae. These snails will slide over the glass, substrate, and ornaments cleaning off any algae that may be growing in your tank. If you allow the pest snails to breed to large numbers, your tank will theoretically be crystal clear and free of algae. For this, I personally recommend the trumpet snails because they hide during the day and only come out at night to feast. This means you can enjoy your tank without looking at ugly snails during the day when the lights are on.