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What to do if Seachem Matrix is not working or not filtering

You can use Seachem Matrix to reduce the ammonia, nitrite and nitrate levels in your fish tank.

If this filter media doesn’t seem to be working or filtering as advertised, then you can take a look at this troubleshooting article from Aquarium Blueprints.

1. The first step we recommend taking is to use an aquarium test kit that can measure ammonia, nitrites and nitrates. Ideally, you should have the following parameters:

  • 0 ppm of ammonia
  • 0 ppm of nitrites
  • Less than 40 ppm of nitrates (or less than 20 ppm of nitrates if you have more sensitive fish)

2. It is very important to note that Matrix does not directly add beneficial bacteria in your tank. Instead, it provides surface areas for these bacteria to cultivate. As a result, it can take many weeks for the product to become effective.

3. It should be much faster to grow the ammonia-consuming and nitrite-consuming bacteria than the nitrate-consuming bacteria.

To speed up the process for all three, you can add live bacteria into your tank. To do so, you can use products such as the Seachem Aquavitro Seed or Seachem Stability.

4. If you are still getting higher than expected nitrate levels, then it may be due to another factor.

For the uninformed Seachem Matrix works best when you keep the nitrate levels to below 40 ppm. At higher concentrations, this biological filter media won’t make much of a difference.

So, if your tank water has more than 40 ppm of nitrates, then we recommend doing the following to gradually lower it in order to make Matrix more effective:

Do small daily water changes of no more than 20% at a time.

If your filter media is dirty, then we recommend rinsing off the mulm with the water you are taking out of a tank during a water change.

If your substrate is covered in mulm, then you can use a gravel vacuum to clean it when you are doing a water change.

Try feeding your fish less so that they won’t produce as much wastes as usual.

Adding live plants should also help lower nitrate levels.

To find out more about how you can safely lower the nitrate concentration in your tank water, you can take a look at this tutorial.

5. You may also want to consider adding more Seachem Matrix as the current ones you are using may be at capacity. By adding more of the biological filter, you will end up providing more surface area for the bacteria colonies to expand.

6. Make sure you regularly rinse your Seachem Matrix as the microscopic pores can be easily blocked by the mulm. If the pores to get blocked, then the beneficial bacteria living inside will end up perishing.

To see how you can properly rinse this biological filter media clean without harming the bacteria, you can take a look at this tutorial.

7. If the Matrix has been in your tank for many years, then there is a chance that its pores may be so clogged up that a simple rinse won’t unblock the openings.

In this case, you can try recharging and regenerating Matrix. To find out how to do so, you can check out this post.