How To Lower Nitrates In Fish Tanks Fast?

The importance of nitrate in the aquarium may not be known by fish keepers than the effects of ammonia and nitrite.

Although it isn’t as lethal in its direct form as ammonia or nitrite, in time the presence of high levels of nitrate can adversely affect fish as well as the aquaculture environment generally.

Nitrates are typically extremely low in natural water partly because of the rate of dilution caused by huge amounts of water, as well as due to water cycles.

How to lower nitrates in fish tanks fast for fish? One common method used to reduce nitrates in aquariums is an alteration of water. However, in actuality, the water change is more of a dilute as opposed to removal.

How to lower nitrates in fish tanks?

Think about this:

Assuming that there’s 40 ppm of nitrate before a 20% water change, then 80% or 32 ppm will remain after the water change. Because common tap water and well water typically have nitrate in them, and assuming the average concentration is approximately 10 ppm the water change did not have any impact on the overall nitrate levels of the aquarium.

What can we do to assist in the removal of nitrates from the aquarium?

  1. Introduce live plants into an aquarium that is freshwater. Plants naturally use Nitrate as a nutrient as well as a food source. This is the reason why persistently high levels of nitrate often lead to an algae outbreak as well as algae-related problems in the water of your aquarium. A high concentration of nitrate can be fuel for the rapid expansion of existing algae cells.
  2. Clean the aquarium The waste eventually produces Nitrate. Clean tanks generate less nitrate which has to be eliminated by water changes.
  3. Cut down on the fish population or make the upgrade to a larger tank
    The waste of fish causes an increase in nitrate levels. The goal is to keep the population of fish at a low level, it helps to stop the accumulation of nitrate. If you’re thinking of getting the possibility of a bigger tank, make sure to avoid the temptation of increasing the number of fish in your tank, since this can increase the nitrate production waste within the tank.
  4. Reduce your feeding
    The overfeeding of fish is a major contributor to the accumulation of nitrate as well as other unpleasant wastes, including phosphate. A large amount of fish food can cause a significant amount of pollution to the water, resulting in an increase in levels of nitrate. Don’t overfeed.
  5. Make use of a nitrate removal product like ALGONE
    A nitrate removal device gently eliminates nitrates in the aquarium and prevents the problems that are common to high levels of nitrate. Nitrate reduction can also remove the cloudiness and murkiness of aquarium water, and restore an enthralling, crystal-clear water column. Furthermore, nitrate remover gets rid of organic contaminants and other dissolved organics caused by rising nitrate levels and other problems that commonly occur in the aquarium fish tank.

Best Nitrate Remover for Aquariums: Our Top Picks

How do you lower the nitrate levels in tanks for fish quickly? Nitrates will not be welcomed in any aquarium. However, using nitrate removers you can eliminate the nitrates from your aquarium quickly with little effort.

Best Nitrate Removers for Aquariums:

  • Seachem Denitrate
  • Algone Aquarium Water Clarifier and Nitrate Remover
  • Fluval BioMax Biological Material Remover
  • Tetra Nitrateminus Liquid

Top 5 Best Nitrate Removers for Aquariums Reviews

Let’s take a brief look at the five best nitrate eliminators for aquariums available to offer today.

Seachem Denitrate: Our Top Pick

Seachem Denitrate 500ml
  • Removes nitrates, nitrites, ammonia, and organics
  • High porosity biological media
  • Pore size well suited for anaerobic bacteria
  • No danger of hydrogen sulfide production as with sulfur based media

Last update on 2024-04-09 / Affiliate links / Images from Amazon Product Advertising API

What we’ve got here is a simple biological filter media. You will find extremely porous biological filtration media you can use inside an aquarium’s filter. Of course, you need to have an aquarium filter that permits you to use your own kind of media, but a lot of filters allow this, like canister filters for instance.

Because of the extremely impermeable properties of this bio-filtering media, it enables anaerobic bacteria to flourish and thrive.

It’s about allowing the bacteria colonies to expand as big as they can be, thus permitting them to eliminate Nitrates, nitrites, and ammonia from the water along with other organic substances.

There’s no need to worry about the creation of hydrogen sulfide because it isn’t an organic filtration medium based on sulfur.

I also love that this product retails at a reasonable cost and has 500 milliliters of water per bottle that should last for a long time. Be aware that the rate of flow in your filter shouldn’t exceed 50 gallons/hour for this type of media.


  • Easy to use
  • Cost-effective
  • Get rid of ammonia, nitrates, and many more
  • Ideal for all kinds of filters.


  • Does not work with cartridge filters.

If you do not have a filter that requires cartridges, this is my first suggestion.

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Algone Aquarium Water Clarifier and Nitrate Remover

Algone Aquarium Water Clarifier and Nitrate Remover, 6 Filter Pouches - 2 Pack
  • Aquarium Water Clarifier and Nitrate Remover, 6 filter pouches

Last update on 2024-04-09 / Affiliate links / Images from Amazon Product Advertising API

This is a fantastic Nitrate Remover that is basically a biological filtration medium. You will receive six filter pouches, each one of which is loaded with biological filters. These pouches specifically designed to are specifically designed to hold bacteria, which will then eliminate ammonia, nitrates, as well as nitrites from the water.

The material in the pouches has been designed in a manner to allow the ideal porosity that allows as many bacteria as possible to flourish. This product is great for absorbing organic as well as toxic substances and pollutants for stimulating the microbial population, breaking down fats, carbohydrates, and proteins, and correcting imbalances in nutrient levels.

In addition, it will not harm algae-eaters, plant snails, fish, coral as well as polyps, birds, live rocks, and many other things. Each package comes with six pouches for filtering which you have to buy at least two pouches. As an aside, the pouches can filter more than 330 gallons of water. They may even aid in clearing up clouds in water.


  • Easy to use
  • Affordable
  • Treatment of large amounts of water.
  • Removes nitrates, and so many more
  • Most filters will work.


  • Does not work with cartridge filters.

If you’re in search of a device that can handle a huge amount of water in a very short time, this might be the one for you.

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Fluval BioMax Biological Material Remover

Fluval BioMax Biological Material Remover, 500 g - Biological Filter Media for Aquariums
  • Filter Compatibility: Compatible with Fluval Filter Series 106, 206,...
  • Water Clarification: BioMax is a premium-grade biological filter media...
  • Ideal Environment: BioMax helps create crystal clear water, making...
  • Versatile: This filter media is suitable for freshwater and saltwater...
  • Additional Features: Will not affect water characteristics.

Last update on 2024-04-09 / Affiliate links / Images from Amazon Product Advertising API

If you have Fluval 106, 206 306 406, FX5, and 105, 405, 305 or 204, 304, or 404 (as similar units) This is an excellent biological filtration media that you can look into. It comes with an alleged complex pore system, which allows the maximum amount of official brand bacteria to flourish and grow.

These are unique biological filtration rings that have significantly more capacity than the vast majority of other kinds of biological media there. They also permit plenty of water movement through this media. This permits the best interaction with water, which results in the most efficient biological filtering.

The thing to take note of is that this bio-based filtration media can be used in saltwater and freshwater tanks. Another thing you might like is that this product won’t alter the chemistry of your water as well as pH. The high-end filtration media will be able to get rid of ammonia, nitrates nitrites, and more from your tank.


  • Achieving optimal growth of bacterial
  • Maximum contact with water
  • User friendly
  • Highly efficient
  • Cost-effective


  • Compatible only with certain models of filter

If you own some of those Fluval filters I have mentioned earlier or models that are very similar This is the most effective nitrate removal filtering media I would recommend.

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API NITRA-ZORB SIZE 6 Aquarium Canister Filter Filtration Pouch 1-Count Bag, Model:110A
  • Contains one (1) API NITRA-ZORB SIZE 6 Aquarium Canister Filter...
  • Removes toxins that can be harmful to fish
  • Removes ammonia, nitrite, and nitrate from aquarium water.
  • Easy-to-use pre-dosed pouch fits most canister filters on the market,...
  • Use when starting a new aquarium and when ammonia or nitrite is...

Last update on 2024-04-09 / Affiliate links / Images from Amazon Product Advertising API

We have a specific kind of biological filter media that was made to be used inside canister filters. The items you receive here are filtration media pouches which have dimensions of 6.5 to 7.5 inches and 0.5 millimeters thick. You must first clean this product with water prior to placing it in your aquarium, otherwise, it could cause discoloration. It is phosphate-free which is a major advantage.

After you’ve cleaned it, just put it in your canister filter and you’re good to go. While it’s not the most cost-effective biological filter media available, however, it’s expected to last for a long time at the very least several months. It’s an extremely efficient type of biological filter media that’s able to get rid of ammonia, nitrite, and nitrate in aquarium water as well as other organic substances.

The most important thing to bear in mind is this has been made to be used only in freshwater tanks and is not suitable for use for saltwater tank installations. It is also rechargeable to extend its use.


  • Long-lasting
  • Cost-effective
  • Great efficacy
  • Ideal for canister filters


  • It requires a canister filter

If you’re looking for top-quality biological filtering media for your cancer filter, this is the right choice.

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Tetra Nitrateminus Liquid

Last update on 2024-04-09 / Affiliate links / Images from Amazon Product Advertising API

Here’s a simple removal of nitrate that you can simply add to the aquarium. It will decrease or eliminate the nitrate. It’s as easy as it gets. All you need be do is adhere to the guidelines that are provided on the package regarding dosage and frequency, and you’ll be in good shape.

There’s nothing more to learn about it. All you need to apply a certain amount according to how big your tank is as well as the level of nitrate There’s nothing more to it.

This is a once-only treatment that reduces the amount of nitrate present in your tank each time you put the liquid in. This is different from biological filters, such as those mentioned earlier that can offer continuous removal of nitrate. It is a fast solution, but it will not solve the root problems.


  • Works very quickly
  • Effective
  • Fish are safe


  • The one-time treatment is not the same as continuous treatment

If you are experiencing extremely high levels of nitrate in your fish tank, and require them to be reduced quickly, this is the best product I’d suggest.

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Nitrate Removers for Aquariums Buyers Guide: What to Look Out For

Let’s discuss a few of the most crucial aspects that you must consider when choosing the right nitrate removal product for your aquarium.

Type – Ongoing vs Immediate

As you’ll be able to tell from the reviews there are two primary choices to consider here. The first is to select the basic biological filter media that are intended to host a colony of healthy bacteria. These organisms over time will eliminate and regulate ammonia, nitrate, and nitrate levels within the tank. This is a continuous solution and something that every tank must include.

It’s referred to as biological filtering. If you’re suffering from very high levels of nitrate that must be removed immediately, the use of a solution like product #5 is recommended as it is an immediate liquid that can lower the nitrate level. However, it is only a one-time solution and not a continuous treatment strategy that is suitable for one-time treatments instead of ongoing maintenance.

Fish and Plant Safety

Make sure the product you’re using is 100% safe for both plants and fish. This is particularly true when you’re using an immediate removal of nitrates which you can pour directly into your aquarium. In this instance, the dosage is something you must be mindful of because the excessive amount of these substances could be harmful to fish and plants.

Replacement and Usage Frequency

If you’re purchasing regular biological media for filtration take note of how long it’s rated to last. Some biological media require to be replaced each month, while other types can last for a longer time. If you are dealing with a nitrate-removing liquid that you can pour directly into the tank make sure you read the directions for use and the time it is recommended to apply the product.

Where Does Nitrate Come From?

Nitrate is a byproduct of nitrite oxidation during the final phases of the nitrogen cycle and is found to a certain extent in every aquarium. Detritus decomposing plant material, filthy filters, overfeeding, and over-feeding the aquarium can all result in an increase in the levels of nitrate.

Furthermore, tap water that is used to fill up the aquarium might contain nitrates. For instance, in the United States, drinking water can contain nitrates that are as high as 40 parts per million (ppm). Prior to adding water to your aquarium, test it for nitrates to determine whether the levels are excessively high in the water source. If the nitrate in your water is greater than 10 ppm think about alternative water sources that are free of nitrate.

Desired Level

In nature, the amount of nitrate present in the water is extremely low, usually well lower than 5 ppm. Freshwater aquariums must be kept clean. the nitrate level must be kept under 50 ppm at all times and in the ideal case, below 25 ppm. If you’re breeding fish or fighting algal growth make sure that the nitrate is kept to a lesser level than 10 ppm.

Effect on Fish

The fish will experience the effects of nitrate as levels exceed 100 ppm especially if the levels continue to rise. The resultant stress makes fish more vulnerable to diseases and hinders their ability to reproduce.

Nitrate levels that are high are particularly damaging to fry and young fish and negatively affect their growth. Additionally, the same conditions that lead to increased nitrate levels often result in lower oxygen levels, which can further strain the fish.

Nitrate and Algae

A high level of nitrate is a key cause of undesirable algal growth and nitrate levels that are as lower than 10 ppm will encourage the growth of algae. The algae blooms that are frequent in tanks that have been set up typically result from increased levels of nitrate.

While plants make use of nitrates when they grow, if the levels of nitrate rise faster than the plants are able to utilize them, the plants could get overgrown with algae, eventually leading to their death and asphyxiation.


What is the fastest way to lower nitrates in an aquarium?

The fastest and most simple method of reducing nitrates in your system can be to alter the water. If the tap water you use has a lower nitrate content than the water in your tank, when you replace the water, the nitrate level will decrease. Check the nitrate levels in the freshwater tank in addition to your tap to confirm that this is indeed the case.

How do I remove nitrates from my aquarium?

One of the most effective methods to reduce nitrates in your fish tank is to change your tank’s water regularly. Other quick methods include the addition of live plants, taking out filters, as well as staying clear of overfeeding or overcrowding.

How can I reduce nitrates without water changes?

If your tank has an elevated nitrate level over an extended period of period, you may apply the nitrate-removing filtering media. Bio-media, which utilizes bacteria to purify the water and get rid of Nitrates, is a good alternative. Bacteria can be classified as anaerobic or aerobic. The anaerobic types can decrease the amount of nitrate.

What can cause high levels of nitrates within aquariums for fish?

Detritus and decaying plant material dirty filters, excessive feeding, and overstocking the tank all contribute to the increase of Nitrate. In addition, the tap water that is used to fill the aquarium might contain nitrate within it. For instance, in the United States, drinking water could contain Nitrate levels that are as high as 40 parts for every million (ppm).

Conclusion: How to lower nitrates in fish tanks?

Though special filters, referred to as denitrators, are available to eliminate nitrate, these devices tend to be quite costly as compared to other filtering units.

How do you reduce nitrates in fish tanks quickly? Instead of buying a costly denitrator or a special filter, it is possible to purchase at your local fish shop a lower-nitrate media to use in the filter you already have. They’ll pull the nitrate from the solution quickly and require it to be replaced regularly.

Dibyajyoti Bordoloi is the creator and author of, a third-generation experienced fish keeper and owner of a successful pet breeding farm. He is also a member of the Center for Wildlife Rehabilitation And Conservation (Assam), the Marine Aquarium Societies of North East India, and the Kaziranga Nature Conservancy of Assam.