A few snails may not harm your tank but an infestation can become detrimental.
Perhaps you have had the experience of looking over your tank one day to find an unexpected guest cruising along your tank wall. Aquarium snails can enter the freshwater tank through a variety of means and, in most cases, they are completely harmless. If you allow these snails to reproduce unchecked, however, a few unexpected guests can turn into a full-blown infestation.
How Snails Enter the Tank
Even if you never purchase an aquarium snail, you may still find them in your tank from time to time. It is possible for aquarium snails or snail eggs to be scooped up along with your fish when you purchase them from the pet store. Snails and snail eggs can also hitch a ride on live aquarium plants purchased from the pet store. If you do not take precautions by cleaning your live plants before adding them to your tank, you could be unknowingly planting the seeds for an infestation.
Effects of Snails
While aquarium snails may not have any immediately detrimental effects on your freshwater tank, if their numbers increase dramatically they could begin to cause problems. Snails naturally feed on decaying vegetation and other forms of detritus so, to a certain extent, they can actually be beneficial for your tank. Many aquarium hobbyists purchase snails like apple snails to help control the build-up of organic waste in their tanks. Once the snails consume existing algae growths and built-up detritus, however, they may begin to feed on your aquarium plants.
In addition to posing a potential threat to your live plants, aquarium snails can also become a general nuisance. After working hard to set up and cultivate a healthy freshwater aquarium the last thing you want is to have dozens of snails creeping along your tank walls and covering your tank decorations. Along with being an eyesore, aquarium snails can also creep into your filter intake tubes which could prevent your filter from working properly. Because snails tend to bury themselves in substrate, coming out only at night to feed, you may not even realize just how bad the infestation really is until it is already out of control.
When you find innumerable snails covering your tank walls and decorations your first instinct may be to run to the pet store and find some kind of chemical solution. While chemical solutions for snail control do exists – and they may, in fact, be effective – they could actually do more harm than good. Chemical solutions cannot target snails specifically. Rather, they will kill all of the invertebrates as well as some of the beneficial microorganisms such as nitrifying bacteria in your tank. If you kill all the beneficial bacteria in your tank it could cause your water quality to drop drastically and the tank could begin to recycle. Not only is this a setback for you but it could also become a dangerous situation for your fish if the ammonia levels in your tank get too high.
There are two safe and natural methods for snail control that you should try before resorting to chemical control methods. The first is to introduce snail-eating species of fish into your tank. Puffer fish and certain species of loach such as yo-yo loaches feed on snails and can help to greatly reduce the snail population in your tank. The second control method is manual removal of the snails. Don’t worry – you don’t have to pluck each snail out of the tank individually. Simply blanch a piece of lettuce in hot water then place it in your tank just before going to bed at night. The snails will be drawn to the decaying plant matter and, in the morning, you will find the lettuce leaf crawling with snails. All you have to do then is pluck the lettuce leaf out of the tank and throw it away along with all of the snails on it.
Because snail eggs are very hard to see, it can be tricky to prevent getting any of them in your tank. The best trick is to soak all new live plants in a salt bath for 10 to 15 minutes before adding them to your aquarium. Exposure to saltwater for such a short period of time shouldn’t harm the plants and as long as you rinse them well before putting them in your tank it shouldn’t affect your tank either. Another option is to look for guaranteed snail-free live plants online and at your local pet store. Some of the larger pet stores have begun to sell individual snail-free plants, though they can cost up to three times as much as ordinary live plants.
Beneficial Aquarium Snails
Not all aquarium snails are bad – in fact, some of them can be incredibly beneficial to have around. Certain species of snails can be very useful in the home aquarium as scavengers, helping to remove uneaten fish food and other waste from the tank before it can break down and affect water quality. Some of the best snails to keep in your aquarium include:
Apple Snail – the apple snail is one of the most common species of snail kept in the freshwater aquarium. These snails come in all colors, but the most common color is blue. Apple snails can grow to be fairly large, up to 6 inches (15cm) in diameter. In fact, apple snails are the largest freshwater snails on the planet.
Nerite Snail – nerite snails are a group of small to medium-sized snails that can be found in both fresh and saltwater. The Zebra Nerite Snail is one of the most popular species for the freshwater aquarium because they are very attractive with their black and gold stripes – these snails also remain fairly small, only growing to about ½ to 1 inch in size. Another advantage of this species is that they are unable to breed in pure freshwater – nerite snails require brackish water to breed, so you do not have to worry about them overpopulating your tank.
Trumpet Snail – trumpet snails have elongated, conical shells with an average of 10 to 15 whorls. The Malaysian Trumpet Snail is one of the most popular species for the freshwater aquarium because they tend to burrow into the substrate and clean out accumulated detritus. Trumpet snails can reproduce in the home aquarium and, interestingly, they produce live young rather than eggs.
Keep in mind that having a few snails in your aquarium is not necessarily a bad thing – in small numbers, snails can actually beneficial. It is when those small numbers turn into large numbers that things tend to get out of control. In order to avoid a snail infestation in your tank, the best option is to soak and rinse your aquarium plants and to check before emptying bags of new aquarium fish into your tank to be sure there aren’t any snails coming along for the ride.