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Is Seachem Matrix any good?

Seachem Matrix is a biological media that that you can put in your filter. You can also drop these rocks directly in the fish tank. So, is this product any good? You can find out in this review article at Aquarium Blueprints.

Quick Summary

Seachem Matrix is among the best biological filter media products you can use. In addition to providing plenty of surface areas to grow beneficial bacteria strains that will consume ammonia and nitrites, these rocks also feature chambers that block off oxygen. In these airless areas, you will be able to grow nitrate-consuming bacteria.

Since you are able to keep nitrate levels at a safe level, you shouldn’t have to do water changes as much as before. Therefore, you can end up saving on your water bill in the long run if you decide to add Matrix to your tank.

The only real drawback is that it can take up to a couple of months for Seachem Matrix to effectively reduce nitrates. Thankfully, you can speed up this process exponentially by using products that contain live bacteria, such as the Aquavitro Seed or Seachem Stability.

If you are interested, you can purchase the biological filter media on Amazon with the following link:


The biggest benefit of Seachem Matrix is its porous structure, which provides plenty of surface areas for the beneficial bacteria strains that will consume the ammonia and nitrites from your tank water.

For the uninformed, any organic wastes in your aquarium will end up becoming ammonia. The beneficial bacteria in your tank will convert ammonia to nitrites and then nitrites to nitrates.

Nitrates are somewhat harder to remove as the bacteria that will consume it will need to grow on surfaces that are devoid of oxygen. To accomplish this, the substrate in your tank needs to be more than two inches in depth. Alternatively, you can use biological media, such as Seachem Matrix, that contains microscopic chambers that are devoid of oxygen.

Without a deep substrate or specialized biological media, the only other options are live plants and water changes. Even with live plants and water changes, the nitrates may end up building up in your tank over time, causing an “old tank syndrome” where it gets so high that it becomes very hard to reduce.

Despite water changes and having plenty of live plants in one of our tanks, the nitrates concentration got to beyond 200 ppm. Even after doing multiple major water changes, the nitrate level would stay the same. It wasn’t until we started using Seachem Matrix in the aquarium that we see the nitrates being gradually lowered to a more acceptable level.

For the uninformed, nitrates should be less than 40 ppm. If you are keeping more fragile species, such as shrimps, then you should aim for less than 20 ppm.

Because Matrix will keep your nitrate levels in check, you won’t have to do as many water changes as before. Therefore, you should end up saving money in the long run as long as you take proper care of the media.

Performing maintenance is easy for this product as you simply rinse it with the tank water you plan on throwing away during a water change. By doing so, you will help unclog the pores while keeping many of the beneficial bacteria alive as possible.

Eventually, you may need to recharge and regenerate the biological media, which should be a simple process. To find out how to do so, you can take a look at this guide.


The biggest issue we have with the Seachem Matrix is that it takes a long time to work when it comes to nitrate reduction. The media does not contain the bacteria strain needed to lower nitrate levels right away. Instead, the bacteria will need to grow on its surfaces naturally in your tank. This process can take many weeks or ever a few months.

To speed up the growth of the beneficial bacteria that will help keep nitrates in check, you can use a supplementary product such as Aquavitro Seed or Seachem Stability.

Another minor problem we have with the Seachem Matrix is that it will make your tank water cloudy if you didn’t rinse it thoroughly before putting it in your tank. Fortunately, the cloudiness should go away quickly if you have a filter running in the tank.