How can I get rid of aquarium snail infestations?

There are a number of methods to control snail infestations.

The Cabbage/Lettuce trap.

       You will need to blanch a piece of cabbage or lettuce and then sink it in your tank overnight. The next morning you can just pick off the snails from the piece of cabbage and repeat the process with fresh lettuce till the numbers come down. This methods is effective against all snails but not against snail eggs. So once you have picked out the adults out , it will be just a matter of time before the eggs hatch out

Loaches

A very good option, if the infestation is in a large tank, but is impractical for smaller tanks, such as nano tanks or planted tanks as loaches have a tendency to dig a little.

Assassin Snails

This in my opinion is the best method for getting rid of snail infestations. Assassin Snails devour the pest snails as a whole, shell and everything, so you won't find a ton of empty snail shells on your substrate. They eat everything, Snails, Snail eggs, hunt them down and eat then away. In my opinion they are the best way to get rid of your snail infestation. And mind you, you needn't get rid of them once they are done with the snails, the assassins will continue grazing on the stray algae, bits of food that may have been left behind, substrate debris and just about anything they can eat. 

Medication

I really wouldn't suggest this method as the medication may kill all invertebrates in the tank and you will have to manually find them and remove them from the water in order to ensure that the water doesn't go bad.

Here are a few steps you might want to take to ensure you wont get the snail problems again in the future.

1. Boil all rocks and driftwood before adding to the tank.
2. Give all live plants a 10% potassium permanganate dip for about 5 seconds. Do not dip the roots in the permanganate solution, just the Stems and leaves.
3. Check the plant leaves for snail eggs(usually small glassy bumps ie in case of the small pest black snails that hitch hike on plants)

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Clinton-Neil