Should I Use Zeolite in My Aquarium? The Do’s and Don’ts!

Zeolite is a great type of media that is usually used to get rid of ammonia and other chemicals from your aquarium.

Many people wonder if using zeolite in the filter all the time is a good option or not.

Opinions may vary regarding this, but the popular opinion is that you should only use zeolite if you’re faced with an ammonia emergency. This can occur if there’s a big spike during cycling or your cycle is ruined by some disaster, like a spoilt filter.

However, zeolite might not be very ideal for long-term usage. Zeolite can only take out ammonia for a month or so before it is exhausted.

To know more about zeolite and how to place it in your filter, read ahead.

What Is Zeolite?

Zeolite is an extremely absorbent and porous mineral. It mainly comprises of silica and aluminum.

Zeolite is widely used in fish aquariums mainly to capture multiple undesirable contents in the water. This highly porous mineral absorbs undesirable elements from the water like a sponge absorbs water. Zeolite is also referred to as ‘a stone that boils.’

It’s important to remember that not all zeolite has been created equally. The process of formation greatly impacts zeolite’s makeup and the applications it is best suited for.

Clinoptilolite, also known as Clino, is a type of zeolite that occurs naturally. It has a high affinity for ammonia, therefore, making it an extremely suitable media material for your aquarium.

Many artificially-created forms of zeolite have also set food in the market in addition to the multiple existing natural forms of zeolite. The artificial form of zeolite highly differs from the natural form of zeolite.

When picking the right type of zeolite for your fish aquarium, ensure that you choose one that is specially labeled for aquarium use only. For example, most cat litter contains zeolite, but it hasn’t been formulated for aquarium use and shouldn’t be used for this purpose.

You will find many types of zeolite that have been formulated for freshwater aquariums only. Additionally, there is also a type of zeolite that is suitable for both saltwater and freshwater use.

Try to opt for those for your aquarium. There are also certain formulas available that contain both activated carbon and zeolite. This combination is highly beneficial for a recently set up aquarium that is facing severe ammonia spikes.

What Does Zeolite Helps Clean the Aquarium?

Zeolite is a great agent for removing toxins from the water, but its main focus is usually on absorbing ammonia. The zeolite that is meant for a freshwater aquarium will easily absorb ammonia, making it a perfect option when faced with ammonia spikes or any other potential spikes.

It is highly crucial to understand that zeolite doesn’t get rid of every undesirable toxin from your aquarium.

It is also important to know that zeolite doesn’t work forever. As a matter of fact, zeolite can become saturated pretty quickly, making it a redundant agent for your fish tank.

Zeolite can get exhausted and redundant within a month or even less. Therefore, the need to replace or recharge it arises. If your fish tank has high levels of ammonia, the zeolite may become exhausted within two weeks or even less.

With elevated levels of ammonia, you will have to test the tank frequently and keep replacing the zeolite as required in order to achieve the desired result. Once you’ve gotten rid of the ammonia, you can remove the zeolite from the fish tank.

Why Should You Not Use Zeolite in Your Aquarium?

Many experts aren’t in favor of using zeolite in a recently set up aquarium. They suggest that biologicals should be given enough time to develop naturally. As mentioned before, only if a severely high spike of ammonia occurs in the fish tank, should zeolite be used for a limited period of time.

Adding zeolite to your aquarium can result in the disruption or the prevention of the nitrification process. The nitrogen cycle or the nitrification process is the creation of good and beneficial bacteria within a fish tank and an aquarium filter.

Leaving zeolite in the aquarium for too long can affect the nitrification process and affect fish life and plant life, which is why it’s recommended to add zeolite only when an ammonia spike occurs.

It is highly recommended to get rid of zeolite once the levels of ammonia drop within an aquarium. It shouldn’t be used on a permanent basis as it can damage the overall environment. Apart from this, it is recommended to replace it with a media, such as activated carbon, to flush out any other substances from the water.

Carbon helps get rid of a variety of things from an aquarium. Some of those elements include odor, colors, medicines, and even organic matter. However, carbon also gets exhausted after a few weeks.

Both zeolite and carbon have to be replaced in the aquarium within a few weeks if you want to keep using them. You can either replace them collectively or separately.

The zeolite that is specifically meant for freshwater should never be utilized in saltwater or any brackish fish tanks. The impact of this on the chemistry of water can prove to be very lethal for corals present in saltwater aquariums. Also, refrain from adding any type of salt in a freshwater aquarium while zeolite is being used in the tank.

Adding salt basically reverses the entire purpose of using zeolite. It causes the zeolite to release all the ammonia that it had previously absorbed. This results in a sudden and very dangerous ammonia spike.

How to Place Zeolite in Your Aquarium Filter?

Zeolite is similar to activated carbon. Zeolite, like carbon, is placed in a bag within the filter. This mineral can either be bought in loose bulk or found in measured media bags.

If you have a canister filter, the zeolite must be put between the foam or mechanical media or the rings and biological media. A few zeolite chips are placed inside a media bag that can be removed or even scattered inside the fish tank later on. This offers a large surface area to nitrifying bacteria.

A gram of zeolite can help get rid of 1.5 mg of ammonia.

A few manufacturers also offer a zeolite pad, which can be cut to fit within a power filter. It can also be placed right next to the foam within a canister filter.

Instead of placing it inside the filter, zeolite can also be put inside a bag that can be hung inside the tank directly into the water flow. This will make it extremely easy for you to remove and replace it, especially if you replace or recharge it very frequently.

Should You Recharge or Replace Zeolite?

Zeolite can either be recharged or replaced. If you want to save money, you can recharge this mineral or replace it. There are various ways to recharge this mineral.

The zeolite that is added to freshwater aquariums can be recharged by soaking it in a 5 percent salt solution. This causes the zeolite to release all the ammonia that it has absorbed. Leave this mineral soaked in the salt solution for at least 24 hours. You can then take it out and spread it out on a tray and let it dry in the sun for at least a day or two.

You can also bake zeolite to recharge it. This method gives much faster results than the former method. You can place this mineral in a baking tray for about thirty minutes to an hour at a temperature of 350 degrees F in order to dry it out.

The benefit of drying out zeolite under the sun is that the zeolite can be left within its original bag. This bag is not safe to expose to high temperatures or harsh conditions; therefore, it can’t be baked.

Once zeolite is exhausted, it needs to be removed completely instead of being recharged. In case the ammonia has faded or is almost gone, it isn’t mandatory to replace the zeolite within the filter.

If you have recharged previously used zeolite, then this should also be discarded within two to three months of use and must be replaced with new zeolite.


The bottom line is that zeolite should only be used for a short time period when an ammonia spike occurs. Once the ammonia reduces and returns to its normal level, it is better to remove zeolite.

It’s better to use alternatives, like activated carbon, if you want to get rid of any other diseases or substances in your aquarium.

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