Fortunately, there is a very easy way to whittle down their numbers in a both a very quick and effective way - all you will need are some veggies! While this method will not completely get rid of snails, it will make their population considerably more manageable on your end. The snails are not considered pests because they actually harm your fish - rather, they are pests because they reproduce at such a quick rate your bioload will be affected (and you won't be able to see through the glass!).
Things You Will Need1. Some type of vegetable
2. A lot of patience
Step 1Wash the vegetables off.
You can either choose to use frozen or fresh vegetables. I personally like using the bags of pre-sliced frozen zucchini and squash because it saves me a lot of time. Either way, you will want to wash the vegetable piece off before you introduce it to your fish tank set up.
Step 2Toss the veggie piece into the microwave.
This doesn't take very long, only a few seconds. Your goal is to soften the veggie piece so that it sinks easily in your aquarium. Blanching it will also make it easier for your fish to eat the veggies as well - they will appreciate the treat!
Step 3Toss it in your fish tank set up and wait.
The amount of time that you leave the veggie piece in your fish tank set up will largely depend on what size it is to begin with - you can severely damage the water quality in a smaller fish tank by leaving food in the aquarium for too long.
For my own tanks I generally leave the piece of zucchini in overnight - I toss it in once I turn out the lights at night and then immediately remove it once I've woken up the next morning. You should see a large clump of snails gathered on the veggie piece of your choice when you go to remove it.
Step 4Throw away the snails and repeat.
Alternatively, you could use them as food for another species of fish if you have any that like to eat snails. Just remember to remove the piece of veggie very carefully from your fish tank set up - if you move too quickly you will just shake off the snails.
Some Final Words on How to Get Rid of Snails
If you can't seem to get rid of snails using the veggie method outlined above, then you may want to consider adding an additional fish to your tank that likes to eat them. However, if this is the route that you take please proceed with caution. Do your research ahead of time and only purchase snail eating fish that can be fully accommodated by your fish tank set up.
For instance, many pet stores and beginning aquarists will recommend adding a Clown Loach or a Pufferfish to your tank to get rid of snails. Please think hard before you do so - there are a lot of fish problems that can arise from either of the above additions!
If you decide on a Clown Loach, keep in mind that you not only will have to accommodate a fish that can potentially reach the size of a football, but at least six of them for it to truly thrive in your aquarium. If you like the idea of adding a school of loaches, there are plenty of smaller species to choose from!
Puffers are generally a bad bet all the way around - most of the commonly available are not a freshwater fish at all, nor are they the ideal candidate for a tropical community fish tank set up because they are very territorial. Adding one will only compound your fish problems significantly - now you will have to worry about both severely wounded fish as well as how you are going to get rid of the snails.
Tips & WarningsI do not recommend any of the commercial snail killers that you will find at your local pet store. In general, they simply do not produce reliable results - at least not in the way that you were expecting them to! While they are almost always very effective at killing pest snails in the aquarium, they are also very good at killing off your fish and other tank inhabitants as well.