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The Best Nitrate Remover for Freshwater for 2022

best nitrate remover for freshwater

Nitrates essentially come from fish waste. When its concentration gets too high, the water becomes toxic. No aquarium owner wants to see their fish go belly up in their tanks. It is the reason why you need the best nitrate remover for freshwater. Your fish will surely be forever thankful that you got one.

The traditional method of lowering nitrate levels in a freshwater aquarium is to change a good portion of the water every week or so. However, it can be quite tiring and there are times when it is not enough, especially if you keep fish that make a ton of waste, like goldfish.

In that case, you will need to use an effective nitrate remover to keep the water as livable as possible. If you are a newbie in aquarium keeping, then the information in the remaining parts of this article may be of help. Let’s start with our short yet useful reviews.


Best Nitrate Remover for Freshwater Reviews

1. Fluval ClearMax Phosphate Remover

fluval clearmax phosphate removers

I have water plants in my aquariums to keep the nitrate levels down, but occasionally, I need to use the API filtration media for lowering nitrates in a freshwater aquarium to a healthy level quickly. The plants help a lot in maintaining nitrate down, but there are still times when they need a bit of help, and this product provides such help.

It does not matter what kind of filtration system you are using for the tank water. This filtration media will effectively filter out all the nasty stuff out of the water. Although it will not fit all aquarium filters, they still fit into most of them. Even if you are not getting a tight fit, as long as the water passes through the filter pack, then it will work properly.

Here is another thing I liked about this product. I can recharge and reuse it for up to two months. Honestly, I have been using the one I got for four months now. It is still working well after every recharge, so I am making the most use out of it.

Aside from keeping nitrates out of the water, this filter medium also keeps it clean and clear. It also prevents the growth and propagation of algae, which can be a huge chore to clean. You will not need to change the water quite as often as before, which is always a good thing.

Now, if you have water plants, you need to make sure that the filter is not doing too good a job. This filter element can get the nitrate level so low that your plants will have not enough nitrates to feed on. So, if you have plants in your aquarium, always check the nitrate levels to make sure that they are not dangerously low.

  • Fits in almost all canister water filters
  • Effectively filters out nitrates and ammonia from the water
  • Can be reused for two months
  • Removes toxins and prevents algae growth
  • Keeps water clear and clean
  • Might make the water nitrate-free, which is bad for aquarium plants

This is a great product if you want to lower the number of nitrates in your aquarium immediately. It is also a great tool to use if your water plants are still in the process of maturing.

2. Natural Rapport Aquarium Water Conditioner

natural rapport aquarium water conditioner

One of the neatest features of this product is that you can use it on both saltwater and freshwater aquariums. This means that if you have one of each, you do not need to buy separate water conditioners. It is a good thing because you do not use a lot of that stuff anyway.

It does seem like aquariums like getting into trouble right before you go to bed. It is always like that with my tanks anyway. Thanks to this product, I no longer need to dump half of the tank out in the middle of the night.

I just need to pour a capful of this nitrate remover for freshwater aquariums and the nitrate level returns to normal the next morning. It truly takes a lot of the hassle out of keeping an aquarium.
In the past, I needed to buy gallons of distilled drinking water whenever I need to replace all the water in my tank. The main reason is that tap water contains a lot of chlorine.

I no longer need to spend a ridiculous amount of money. Just a cap of this water conditioner per gallon of tap water is enough to remove most of the chlorine and makes it safe enough to keep fish in.

Aside from removing chlorine and nitrates from the water, this water conditioner can also adjust the pH level of the water to make it ideal for keeping fish. Also, you will be adding the much-needed electrolytes and a slime coat to the water, which mimics natural conditions that fish love.

Now, you need to be cautious when using this product on an aquarium with plenty of live plants. You may lower the nitrate level too much that you will not be leaving enough of it for the plants, causing them to wilt and die.

  • Can be used on freshwater and saltwater aquariums
  • Immediately gets rid of nitrates and ammonia
  • Makes tap water aquarium-friendly
  • Normalizes the pH level of the water
  • Adds electrolytes and a slime coat to the water
  • May put the nitrate level at a dangerously low level, which is not good if you have aquarium plants

Overall, this is an all-in-one solution for keeping your aquarium clean and safe for your fish. However, remember to use it sparingly if you have plants in your tank because it might pull too many nitrates from the water and leave nothing for the plants.

3. DrTim’s Aquatics NP-Active Pearls Media Reactors

drtim's aquatics np-active pearls media reactors

Even if you are a heavy feeder or if your fish produce a lot of waste, like how goldfish do, you still need a nitrate remover for your tank. I have a 50-gallon reef tank, and the nitrate reading is always around 10ppm or less for weeks now. In the past, the nitrate level would skyrocket to more than 40+ ppm in just a week.

It does not matter what kind of tank you are keeping. Whether it is a saltwater or freshwater tank, these media reactors can help you maintain safe nitrate levels in freshwater aquariums. Also, because there are no chemicals involved, just a natural reaction, it is perfectly safe for corals and small fish.

Note, however, that you need to clean the reactor quite often because it will fill up with slime rather quickly, especially if you keep fish that produce a lot of waste. It helps to keep the water in my tank crystal clear. I didn’t get the chance to clean the glass of my tank for a week now, and I don’t think I will need to do so for yet another week or so.

Before, I had to change half of the water in my tank every week just to get the nitrate levels under control – that is with a filtration system already in place. After I included this product in the system, I noticed that the nitrate level is still low enough even after a month that I do not need to replace the water yet.

Now, here is the problem – if you have a small tank, then it may not be a good fit for you. You will need a good protein skimmer on top of a good filtration system because it will create a lot of slimes that will clog up your filters.

  • Removes nearly all the nitrates in the water
  • Works in both freshwater and saltwater tanks
  • Keeps the water in the tank clear
  • All-natural and uses bacteria to get rid of excess ammonia and nitrates
  • Keeps the nitrates and phosphate levels consistently low
  • You will need a good protein skimmer because it may clog your filters

Undoubtedly, this product can remove almost all the nitrates in all kinds of aquariums. However, you need to have a good protein skimmer and a reactor to make it work properly.

4. Tetra EasyBalance Conditioner

tetra easybalance conditioner

This is the product that you need if you want to keep your aquarium in tip-top shape. Assuming you already have your aquarium set up just the way you like it, using Tetra EasyBalance will not only maintain it but will also improve the water quality quite a bit.

If you notice that the nitrate level in the water is rising quite a bit, using this product will get it back down gradually. It will prevent stressing the fish in the tank too much. If you have a planted aquarium, I suggest that you use this product sparingly as it may disrupt the nitrate cycle too much and cause the plants to die.

As mentioned earlier, this product will add nutrients and vitamins to the water. It will act as a supplement for the fish to keep them healthy. However, keep in mind that you should only use it once a month. Use too much and it will foul the water.

Another thing I like about it is that it is very easy to use. You just need to use the cap to measure the amount of the product you need to use. Remember that you will only be using a minimal amount, like a capful for every 10 gallons of water. This product is potent and may harm your fish if you use too much of it.

Now, if you use even a bit too much, like a full capful for a 5-gallon tank, it will turn the water cloudy for a couple of hours to a full day. Your fish will be perfectly fine for the duration. However, it may look a bit scary to see the water in your aquarium turn cloudy like that.

  • Helps maintain a healthy balanced aquarium environment
  • Effectively removes nitrates from the water
  • Adds beneficial nutrients to the water
  • Easy to use
  • Optimizes the water’s pH balance
  • Makes the water temporarily cloudy

Don’t expect too much from this product as it is meant for maintaining an already healthy tank. It would not do much if you need to lower the nitrate and phosphate from the water immediately.

5. Brightwell Aquatics MicroBacter7 Conditioner

brightwell aquatics microbacter7 conditioner

If you are starting a new aquarium, I highly advise using this product on it before you place the fish inside the tank. This product contains helpful enzymes and bacteria that will help jumpstart the natural bacterial filtration system in the tank. After a short while, you can put the acclimated fish into the water.

If you discover that your aquarium suddenly has a high nitrate concentration, then you need to use this product right away to lower the toxicity of the water. Just a little bit of this product will go a long way, and it will immediately lower the nitrate level to a safe level almost instantly.

Countless veterinarians have tried and tested this product and they all recommend its use. This product does not contain any harsh chemicals, just natural microbes, and enzymes. It is not this product that removes the nitrates from the water. It encourages the growth of bacteria that get rid of nitrates.

Aside from removing nitrates and other toxic chemicals from the water, it also improves oxygen concentration. It is the ideal product if you are running a no-filter, no-aerator tank. However, since your fish relies on aquatic plants for their oxygen and food, make sure that you do not drop the nitrate level too much; otherwise, you will kill your plants.

Now, here is an issue with this product. Just looking at how long the instructions are, you will already know that it will be complicated to use. If you are a beginner, make sure that you read the instructions carefully. Use only the required amount of this product, or less just to be sure.

  • Quickly conditions the water in the aquarium
  • Greatly reduces nitrates, phosphates, and other organic carbons
  • All-natural product and uses microbes and enzymes
  • Increases the oxygen concentration in the water
  • Establishes a biological filtration cycle
  • Might be too complicated to use for beginners

Although this product is a bit complicated to use, it is still not a rocket-science level of difficulty. You will eventually get used to using it in no time. It can help keep your aquarium water clear and almost nitrate-free for a long time.

6. Aquarium Nitrate Remover Pad

aquarium nitrate remover pad

You will be getting a rather large sheet of nitrate removing filter media, so you can just cut a piece to fit whatever brand of filter system you are using. It is unlike the other brands that were already pre-cut to fit “most” filters.

However, it also means that you may be wasting a bit of the product if this sheet can only make one or two filter sheets for your tank. With that said, it would be better to cut carefully to reduce waste.

Aside from removing nitrates, this filter medium is also great at trapping small bits of organic matter. If you tend to overfeed your fish or your fish produces large volumes of waste matter, then you should consider getting this filter medium. You would essentially be hitting two birds with one stone.

Although it does filter out nitrates, do not expect it to lower the nitrate level immediately. Also, this filter does not get rid of that many nitrates and phosphates. However, it is still a good filter medium to use for maintaining your aquarium at tip-top shape. It helped me a lot by minimizing the frequency of water replacements.

Also, this filter medium seems to last much longer than other kinds of filter media that I have used so far. One square can last me for a couple of weeks, compared to the other cheaper brands that require replacement every week. Although these filter pads are a bit on the expensive side, you will be getting your money’s worth.

As mentioned earlier, this filter medium is not that great at removing nitrates as it claims. If you are looking into immediate nitrate removal, it is best to try other products. This filter medium is best for maintaining ideal nitrate and phosphate levels.

  • You can cut it to fit all kinds of filter systems
  • Can trap small organic particles
  • Helps lower the nitrate level of the tank
  • Safe for use in both freshwater and saltwater tanks
  • Can last for weeks
  • Not ideal for large nitrate concentration

Although this product supposedly lowers nitrates, it will need assistance from other nitrate-lowering products. However, it is great for maintaining an already flourishing aquarium.

7. Kolar Labs Metabolix Bio-Pellets

kolar labs metabolix bio-pellets

These bio-pellets are made from all-natural ingredients, mostly resin made from corn. You will not be adding any chemicals into the water, so you are sure that your fish will all be safe.

I have a reef tank at home, and keeping it balanced is quite difficult. I was so glad that the Kolar Labs bio-pellets were able to reduce the nitrates in the water without stressing the fish or the corals.

Speaking of nitrate levels, I was quite surprised that the nitrates in my tank were almost zero ever since I started using these bio-pellets. I can see by the way all my fish seem to be swimming happily and how the corals have brighter colors. The water is so clear that it sometimes seems like my fish were floating in midair.

I have tried other bio pellets before, but none of them were as easy to use as Kolar Labs. I just placed the recommended number of pellets in my reactor, and they tumbled almost right away. The shape of these pellets makes them tumble over each other in the reactor, allowing the process to start immediately.

This product is ideal for both freshwater and saltwater tanks. However, you will need to use a protein skimmer to get the best results. For freshwater tanks, though, just the bioreactor is enough.

These bio pellets will not harm any of the fish or corals in your tank. However, this might lower the nitrates too much for live plants so you will need to supplement the water with nutrients.

The only problem that I have with this product is that the pellets clump up after just a day, even if the nitrate levels are just a bit over 5ppm. It means that you will need to replace the pellets a couple of times until they do not create as much slime as before.

  • All-natural solution to high nitrate and phosphate
  • Keeps the nitrate level to almost zero
  • Easy to tumble in the reactor
  • Safe for both saltwater and freshwater aquariums
  • Keeps the water crystal clear
  • Clumps up quicker compared to other bio pellets

Overall, I can say that it is the best solution if you need to remove the nitrates from a large aquarium, like 30 gallons or more. Truly, it is a more hassle-free way compared to replacing half of the tank’s water every week.

8. Seachem Denitrate

seachem denitrate

I have a tank with a couple of goldfish, and as most aquarists can tell you, they make a lot of waste, leading to very high nitrate concentration. De*nitrate helped to drop the nitrate level from a staggering 80ppm to almost 0 in just one day. I now regularly use this product and my goldfish tank consistently has almost 0 nitrates.

I also use this product in a tank that has live rock, and it does not seem to have any negative effects on them, at least nothing that I can notice. The live rock is still thriving and the other fish in the tank seem happy and healthy as well.

Unlike other nitrate treatments that are hard to measure properly for small tanks, this product is not. If you closely follow the instructions, you can figure out easily the amount of product you will need on any size tank. I also use this product on a small goldfish bowl and it has been working well so far.

This product is also versatile. You can only use nitrate treatment products on certain types of filtration systems, but De*nitrate is fine with whatever filter you are using. Whether you are using a canister filter, chemical filter module, or a box filter, it is not a problem with this product.

Now, the problem with this product, especially if you are a beginner, is that it is hard to understand the instructions. You also have to be accurate at measuring to make sure that you are not using too much or too little. However, in my case, I just start with a small amount and then add more if I think the tank needs it.

  • Proving effective in removing nitrates
  • Safe for live rocks and sand
  • Ideal for use on large and small tanks
  • Usable in different kinds of tank filters
  • Long-lasting
  • Comes with complicated and vague instructions

Seachem is famous for its excellent aquarium treatment products, and the De*nitrate is not an exception. You need this product if you constantly have trouble controlling the nitrate level in your aquarium.

9. Kordon 31256 AmQuel Ammonia Detoxifier

kordon 31256 amquel ammonia detoxifier

I live in an area with heavily chlorinated tap water that it is even possible that you will smell it sometimes. This means that as is, the water is not suitable for use in aquariums or even as drinking water for pets. With just a couple of drops of AmQuel in a couple of gallons of tap water, I discovered that chlorine simply goes away in just a few minutes.

Aside from chlorine, this product also removes other harmful chemicals from aquariums, like nitrates and ammonia. There was a time when a freak lightning storm completely totaled my aquarium’s filtration system, causing ammonia and nitrate levels to spike dangerously. It saved my fish and kept them healthy until I fixed the filters.

I have a couple of aquariums – two 50-gallon tanks and one 150-gallon. At first, I thought one bottle of AmQuel would not last long, but after a couple of months, I still have around a third of the bottle. You will only need a couple of capfuls to treat a large tank’s worth of water, and a few drops for lowering nitrates in a populated tank.

This product is also easy to use. Unlike other water treatment solutions, you do not have to use any fancy equipment or do anything else to prepare the water. The only thing you have to do is to measure the appropriate amount of this stuff depending on the amount of water you want to treat and wait a couple of minutes to let it work.

Now, there is not much to complain about with this product. However, you need to know that it will take a while to get rid of ammonia, usually a couple of hours depending on the amount. If you are going to use it in an aquarium with a high ammonia level, wait a couple of hours, take a reading then decide if you need to put in more.

  • Eliminates chlorine from tap water almost immediately
  • Can effectively remove ammonia and nitrates
  • A little goes a long way
  • Easy to use without any other preparations needed
  • Safe for use on tanks with live plants
  • Takes a while to get rid of ammonia in large tanks

This product is a must-have for all aquarists regardless if you are a beginner or have been in the hobby for years. You will always need a product to remove toxic chemicals in the water, so you should always have a bottle of this product.

10. API ZORB Filtration media NITRA-ZORB

api zorb filtration media nitra-zorb

If you use any kind of cartridge filter system to keep your aquarium clean, you can add this product for removing nitrate from the freshwater aquarium. Clearmax comes in 2-inch bags that you can insert into your filter systems (might be a tight fit for some) and it will immediately get to work removing toxic chemicals out of the water.

This filter cartridge is a little workhorse. It can get rid of a large number of toxic chemicals from my aquarium. I have a 50-gallon tank that suddenly got a huge spike in ammonia and nitrate levels. After just a night of using this filter, the ammonia dropped to zero. Moreover, I was able to make use of that one filter for an entire month.

Aside from keeping my fish (and plants) happy, this product also kept the water crystal clear for the longest time. It has been two weeks since I started using it and my tank looks like it just had a complete water replacement. It also prevents algae from forming so I rarely need to clean the tank. It made keeping an aquarium a whole lot easier.

Although the primary purpose of this filter media is to remove harmful substances from the water, it also acts as an additional layer for filtering solids from the water. Before, I replaced half of the water of my 50-gallon aquarium weekly, but thanks to this product, I only do it every month.

As I mentioned earlier, if you have a larger filter, then you may not have any trouble getting it to fit. However, if you have a smaller model, then you may have to be creative to make it fit.

  • Compatible with different kinds of cartridge filters
  • Can absorb a great deal of ammonia, phosphates, and nitrates
  • Keeps the water clear and prevents the growth of algae
  • Adds another layer of solid filtration for multi-stage systems
  • Lasts for at least a month
  • It may be challenging to fit in smaller filters

This product helps make aquarium keeping a lot less of a hassle than it once was. It keeps the water clean and safe for fish and lessens the frequency of water replacement, which is always a good thing.

What to Look For When Buying a Nitrate Remover for Freshwater

removing nitrate from freshwater aquarium

If you are still a bit confused about which type of nitrate remover to buy, here is a quick guide to help you make a choice.

Saltwater or Freshwater?

What kind of setup are you running? Do you have a saltwater reef tank or a freshwater tank that has live plants? Although some products can work on either saltwater or freshwater aquariums, it is best to get one made for a specific kind of setup.

Filter Media or Water Conditioner?

This will usually depend on the size of the tank you are treating. If you have a large tank, like 50-gallons and up, and you have a rather large filter system, you can use filter media. If you have a bioreactor, you can also use resin pellets. It is suitable for high-ammonia setups.

On the other hand, if you have a small tank, like 15 to 20-gallons, you can use water conditioners. These are products that contain natural enzymes that break down harmful chemicals in the water.

Ease of Use

If you are a beginner aquarist, then you should get a product that is not too complicated to use. You may see a lot of experienced aquarists in online forums rave about a certain product but upon receiving the product, you discover that it is difficult to use and requires a bit of preparation.

With that said, if you are someone who does not have that much experience with aquariums yet, you should just stick with water conditioners.


Aquarium keeping is an expensive hobby. A good tank and accessories can already run you up a couple of hundred dollars. If you have a limited budget, then you should get a nitrate remover that will not break the bank.

However, that does not mean you should get the cheapest one that you can find. You should also consider the effectiveness of the product; otherwise, you will be wasting your money.

Frequently Asked Questions

lowering nitrate levels in freshwater aquarium

How to Lower Nitrates in a Freshwater Aquarium?

If you do not want to add anything into the water or do not have room in your budget for a fancy filtration system, you can place a couple of live plants in the tank. However, if you want something that works a bit faster, consider using a water conditioner.

What is the Fastest Way to Lower Nitrates in a Freshwater Aquarium?

If you can afford it, you should get a bio pellet reactor. It can help remove nitrates and ammonia from the water quite quickly and will keep it that way for a long time. However, some water conditioners work quite fast as well. Some of them will even give you positive results after an hour or two.


Responsible aquarium owners should always check the nitrate levels of their tanks regularly to make sure that their fishes are healthy and happy in their artificial environment. However, there are times when, even with your best efforts, nitrate levels will spike to a dangerous level.

When that time comes, you need to have the best nitrate remover for freshwater (or saltwater) aquariums. There are many kinds of nitrate removers that you can choose from, but not all of them work the same way. Some are better than others. With the help of this guide, you will be getting the former rather than the latter.

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