Will Snails Help Cycle The Fish Tank?

You are starting a new fish tank, and you know you have to let the tank be cycled before adding any fish. How about snails? Can you put them in before the tank is cycled and will they even help with the cycling of the fish tank?

Snails will not noticeably help with the cycling of a fish tank. They will provide a small amount of ammonia from the waste they produce to build up beneficial bacteria and help the cycle. But it’s not enough to do an impact on the cycling of the fish tank.

The snails will help somewhat with the cycling, but how is the cycling working and why is it that the snails will help a little bit, but not a lot with the cycling of the fish tank?

What Is Fish Tank Cycling?

The cycling of a fish tank is the act of letting the beneficial bacteria, living inside the fish tank and in the water, build up to keep the levels of ammonia and nitrite down when adding fish and other inhabitants into the fish tank.


Every animal or organic material you put into the fish tank will add ammonia into the water. Ammonia is produced by bacteria when proteins and waste products from animals are being broken down.

These ammonia producing bacteria are present in the water and on eveything from the brginning. The problem is that even a small amount of ammoina will be harmful and kill your inhabitants in the fish tank.

In the wild, the ammoina will be diluted into the sea while in a fish tank where the amount of water is much smaller we need to handle the ammonia in order to not get a spike.

This is where the cycling comes into account!


Next step in the cycle is that another bacteria start to break down the ammonia.

This is what you want since the rest product of breaking down ammonia is nitrite which is not as harmful for the aquatic life as ammonia are.

It’s still harmful though. Too high amount of nitrite will harm the life in a fish tank and potentially kill your fish, snails and shrimps.

There is one more step to be needed to make the environment a lot more safe for the animals. You have to convert the nitrite into nitrate.


The last step is to convert the nitrite into nitrate. It’s easy to confuse these two since they have such a similar name.

The nitrate is also produced by bacteria and is the rest product of bacteria breaking down nitrite.

The nitrate is a lot safer for the life in the fish tank and is consumed by the plants which needs it to be able to grow properly.

A lot of nitrate is also removed when doing water change. Although, if it’s too much built up nitrate the fish will be harmed. Therefore it’s imprtant to do the water changes.

If you are uncertain of how to do a water change, I have a complete step by step guide on how to do a water change.

The act of cycling the tank before adding any living animal is to make the water quality safe for the fish. You have to build up the colony of the bacteria breaking down the dangerous waste products.

How To Cycle The Tank

To cycle the tank, just add small amount of ammonia into the empty fish tank. Be sure you have the filter on because most bacteria are living in the filter.

To add ammonia you could just simply put a small amount of fish food int o the water. The food will fall to the bottom and break down.

When the food is broken down the ammonia will be produced and the cycle begins. The bacteria are building up and be more in numbers and by that more effective at breaking down the rest products.

To be sure the cycle is done, you should measure the nitrite levels with a nitite test.

The one from API is easy to use and are accurate. You could cet it on Amazon here.

If the nitrite is 0 ppm, you know the bacteria are breaking down the nitrite into the more safe nitrate and you know the bacteria colony is sufficient enough to hande the waste from the fish.

Usually it takes a couple of days, I would recommend to let the tank cycle a little bit more, usually 1-2 weeks to be sure the bacteria are strong.

Once the tank is cycled, you can add fish or other inhabitants into the fish tank. If you add too much fish at once. They will produce more waste adn the bacteria could have a hard time keeping up with breaking it down and that’s a risk of an ammonia spike.

If you get an ammoina spike, your fish will most certainly die.

How about snails?

The snails will also produce waste but not the same amount as fish will.

When To Add Snails To Fish Tank?

By adding snails in the cycling phase of the tank you help the tank to add a little bit of ammonia which helps the bacteria to grow.

The ammount of ammonia will not be as much as if you add fish food into the water. Most effect will be from the addeed fish food.

By adding snails you run the risk of the snails eating the food and thus reduce the amount of ammonia coming from the food.

This could make the cycling process take a little bit longer.

If you have snails added in the cycling phase you should put a little more fish food into the water to provide more ammoina for the bacteria to break down.

By doing so, you run the risk of your snail dying due to the ammoina spike, which they are sensitive for. And if a lot of snails die at once, you will have a lot more waste products and make the cycling harder.

It could also be that, when yuou provide more food, the snails will eat more food and when they eat more food, they reproduce more and you could get a snail infestation even before adding any fish.

The safest bet is to add snails when the tank is cycled.

By doing so, you give the tank the time it needs to make the water quality good for every inhabitant in the fish tank.


I have been a fish keeper a big part of my life. During the years I have gathered and searched a lot of information about fish keeping and here, on the website, is where I share that information to help you with your fish keeping. I want to provide the information that I didn't get when I had a question about my fish tank.

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