Best Nitrate Remover for Freshwater

Best Nitrate Remover for Freshwater

Nitrates, those pesky little things that can wreak havoc on the health of our fish. In small amounts, nitrates are harmless.

They are a natural occurrence that is part of the nitrogen cycle in our tanks. To understand the harm nitrates can do, we must first explore the nitrogen cycle and what that means for our tanks. 

Science lesson time! The nitrogen cycle is what happens when the waste excreted by your tank life breaks down. The waste breaks down and gives off ammonia.

This ammonia is then broken down by a bacteria called Nitrosomonas. These bacteria transform the ammonia into nitrites (note the subtle change here, nitrites are different from nitrates).

When the nitrites have formed, another bacteria called Nitrobacter feed on them, transforming them into nitrates

As you can see, the presence of nitrates in your tank is completely natural, and a normal part of the nitrogen cycle. However, if the nitrate level surpasses what your tank can cope with, it can start to have an effect on the health of the creatures that inhabit it.

Now, it must be noted that it is unlikely that a sudden spike in nitrate levels will kill your fish outright, although more care should be taken for particularly sensitive fish or coral.

That being said, the health effects that can be caused by excess nitrate levels can actually cause issues that may then lead to death.

Best Nitrate Remover for Freshwater

For example, an increase in nitrate levels in your tank can be very stressful for your fish, and may even increase the risk of them getting diseases. It can also affect how well they grow, and even the color of your fish. 

We are sure that you can agree that it is important to undertake regular nitrate removal in your tank. Luckily for you, there are products that are designed to do just that.

In this article, we are going to be telling you all about five of our favorite nitrate removers for freshwater tanks.

We have ranked them starting with the best of our top picks, giving each of them a review and a list of pros and cons.

We also thought it would be helpful to include a Buyers’ Guide, which consists of a list of features that we looked out for when we were picking out our top products.

These will help you know what to look for when you are buying your own nitrate remover. So without further ado, let’s get into it. 

Are you in a hurry to get those nitrate levels down? Look no further because Seachem Prime Fresh and Saltwater Conditioner is the product for you. Here’s why it’s our top pick: 

  • Seachem is a reputable brand with over 30 years of experience in the field and an excellent customer care team who will help with any queries you have 
  • The water conditioner is simply to use and has very easy to follow instructions on the back, making it ideal for beginners who are looking after their first tank 
  • Not only does it reduce nitrate rates, but it can also help control the amount of chlorine and chloramine in your tank, as well as binding together any ammonia, rendering it non-toxic 
  • It encourages natural slime film production so you do not need to rely on artificial sources.


Seachem Prime 1000ml

First on our list, we have the very highly rated Seachem Prime Fresh and Saltwater Conditioner.

This conditioner does wonders for our tanks because not only does it help to remove nitrates, but it can also help control the amount of chlorine and chloramine in your tank.

It also helps the biofilter to stop harmful ammonia from your tank. It is also very detoxifying, benefitting your tank and the creatures in it.

It can also help to promote the natural production of slime coats in your tank, rather than having to rely on artificial sources.

It has easy to follow instructions on the back so you will know exactly how much to use in the environment of your tank. 


  • A reputable brand with over 30 years of experience in the field, using science as their knowledge base for pet care 
  • It is easy to use for beginners who have just started their tank and fish journey due to the easy to follow instructions
  •  Not only does it remove nitrates, but it also renders harmful ammonia non-toxic, as well as controlling the amount of chlorine and chloramine. 
  • It can help to promote natural slime film production


  • Lots of fellow fish tank owners have remarked on the bad smell that this product has, so please bear this in mind if smells tend to bother you


Seachem Purigen Organic Filtration Resin - Fresh and Saltwater 100 ml

This product is a resin based nitrogen removal by Seachem. That’s right, they have made it onto the list for a second time!

This product works to remove not only nitrates from your tank water but also excess waste produced by all living things in the tank.

It helps to make the water crystal clear and safe for your creatures to inhabit.

Once the substance has been used up and it does not seem to be removing the nitrates any longer, you can actually regenerate the Purigen using a solution of bleach and water (following strict instructions set by the manufacturer of course).

You will know it has stopped working when the resin turns from a pale white-ish color to a dark brown. 


  • It can be regenerated after it has been used initially with a solution of water and bleach and then reused as long as there is no strong smell of bleach (conduct a chlorine test on a small amount of it first) 
  • As well as getting rid of nitrates in your tank water, it can also help to improve the overall color of it, achieving a crystal clear color that we all desire 
  • As we mentioned in the first product, Seachem is a reputable and trusted brand that has lots of experience in this field, so you can buy this product knowing you are in good hands. 
  • It works quickly at clearing the tank in emergencies


  • Most of the lower score reviews for this product by fellow tank enthusiasts mentioned that they had issues with the packaging of the product upon arrival, namely, the bags of the resin had holes in them for a number of people 


API NITRA-ZORB SIZE 6 Aquarium Canister Filter Filtration Pouch 1-Count Bag, Model:110A

Next on our list the Nitra-Zorb by API. API is a trusted brand that is known for their high quality products for our fish tanks.

Their product can help to remove a number of toxins that can be harmful to your tank life such as ammonia, nitrites, and nitrates.

If this is left in the water it can have an effect on the health of your fish and also cause excess algae growth, which will affect how your tank looks.

The pouch fits in most canister filters that are available to buy for your tanks, and it is a one dose size so it takes out the guesswork when it comes to administering the product in your tank.

Just pop the whole pouch in and your job is done! 


  • It removes harmful toxins from your tank that could otherwise harm the life in your tank such as ammonia and nitrites as well as nitrates. 
  • It comes in a one dose pouch size so you know exactly how much to put in 
  • It can help reduce algae growth which can make your tank look dirty and off color 
  • They are a trusted and reputable brand


  • If you do not have a canister filter this product will not be suitable for you as it is only designed for those. 


TankFirst Complete Aquarium Water Conditioner - Fish Water Conditioner, Instantly Removes Chlorine, Chloramines, and detoxifies Ammonia from Fish Tanks Without The Awful Smell, Made in The USA

Next up is another Water Conditioner, but this time it is by TankFirst. This complete treatment does more than just remove nitrates from the water.

It also tackles chlorine and chloramine, removing them from the water. As well as this it binds together the ammonium in your tank, rendering it harmless as it turns it non-toxic.

It is very easy to use the product which makes it perfect for beginners that are scared of messing up the amount of product they need to use in their delicate tanks.

It also boasts an odorless formulation which will be a relief for some tank owners who are fed up with strong and foul smelling products. 


  • Easy to use with simple instructions to follow 
  • Not only does it remove nitrates from your water, but it also tackles nitrites, ammonia, chlorine, and chloramine
  • A perfect product for beginners 
  • Odorless formulation


  • Some customers reported that it didn’t work as quickly as they wanted, and some even said that they saw no effect on the ammonium levels and nitrate levels in their tanks. These customers are few and far between and the product has much more high reviews than low ones, even so, it should still be taken into consideration 


Seachem Denitrate 1 Liter

Last on our list is yet another product by Seachem. What can we say? They just know exactly what fish like!

This time we have their Denitrate, a product that was made for the specific reason of getting rid of nitrates from the tank.

It provides support for your biological filter and also helps to rid the tank of harmful ammonia, chlorine, and chloramine.

Each liter bottle can treat up to 100 gallons of tank water. It is also easy to use, making it perfect for beginners as well as long time fish enthusiasts.

As we have already stated, Seachem is a very trusted brand name in the market, so you can rest easy knowing you are in the hands of a reputable manufacturer. 


  • The product is made to help create a biological filter for your tank in order to get rid of harmful nitrate levels. 
  • As well as nitrates, this product can also rid your tank of ammonia, nitrites, chlorine, and chloramine 
  • It is easy to use which makes it a great product for those who have their first starter tank 
  • The brand is trusted and their customer care team are extremely helpful should any issues arise with your product


  • Some customers have found that it takes a long time to work and does not drastically reduce nitrate levels as they had hoped. With this in mind, this product may be better suited to those who don’t have nitrate levels that are at a crisis level 

Best Nitrate Remover for Freshwater Buying Guide

Type of nitrate remover 

There are a variety of types of nitrate removers to choose from. Consider what type would be most beneficial for you.

Typically you can choose from nitrate pads, water conditioners, nitrate sponges, and nitrate tablets. Here is a quick overview of each of them:

  • Nitrate pads - As well as removing nitrates, these pads can also remove debris, food particles, and organic particles that are left in the water.
  • Water conditioners - These nitrate removers also work well for saltwater tanks as well as freshwater tanks. They can also neutralize chlorine levels in the water.
  • Nitrate sponges - These sponges can absorb ammonia and encourage the growth of good bacteria all whilst doing their job of lowering nitrate levels.
  • Nitrate tablets - They can promote oxygen intake as well as lowering nitrogen levels. 

Check the ingredients the remover uses 

As with any product you introduce to your tank, you must ensure that the ingredients in the nitrate remover are suitable.

Make sure that the nitrate remover you choose has natural ingredients in there that will benefit your fish as well as reducing the nitrate levels.

Some removers state that they use biological ingredients. A common feature of nitrate removers is sodium hydrosulfite (also known as complexed hydrosulfite salts).

This would be a good ingredient to look for. Above all, we would always recommend checking the reviews on each product to see what fellow tank owners say about it. The products we have chosen have all come highly recommended by other fish enthusiasts, too. 

Is it versatile? 

This relates a little more to the first section on the Buyers’ Guide.

As you know now, each type of nitrate remover does slightly different things in that it can benefit your tank in more ways than just removing nitrates. you could look for products specifically for their versatility, choosing one that will help reduce chlorine levels, for example.

Some of them also have the capability to remove excess debris from food and waste as well as lowering ammonia levels in your tank, all of which can cause harm to your pets within the tank. 

Reputable brand 

We cannot stress enough the importance of buying from reputable brands. Us fish enthusiasts spend a lot of time and money on our beloved tanks and the creatures in them.

Buying a cheap product from a brand you have never heard of may seem like a good idea in terms of money saving, but is it really worth risking the overall health of your tank? Buy from brands that you have used before, or leading names in the industry.

As we mentioned earlier, check the reviews of all products before buying anything for your fish tank.

This is not to say that a lesser known brand will not have a good quality product, though! The important thing is that you do your research, gathering opinions from other customers, as well as reading extensively about the brand and the product itself. 

Final word 

There you have it, our Top Five Picks for the Best Nitrate Remover for Freshwater Fish Tanks.

We’re sure you can agree by now that getting a nitrate remover for your tank is absolutely essential. As part of the nitrogen cycle, nitrates are a normal occurrence in your freshwater tank - no matter whether you have bettas, guppies, or any other freshwater fish.

However, if they are not regularly removed, these nitrates can build up in harmful amounts, having a nasty effect on the health of your aquatic life.

Conducting regular nitrate tests in your tank and then following up with nitrate removal is the best way to ensure that your tank is a safe and healthy environment that your fishy friends need.

As well as this, almost all of the nitrate removers out there can also help to remove other harmful substances from your tanks such as chlorine, chloramine, ammonia, and even nitrites that haven’t yet been converted to nitrates. 

Remember, whatever nitrate removal product you choose, it is absolutely essential that the instructions are followed completely or else you risk causing further harm to your tank.

If our top five picks have not given you the product you need, don’t worry because you can use our handy Buyers’ Guide to ensure that the product you do buy will be of the best quality possible. 

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