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How to fix ‘sensing air in filter’ issue with Fluval G3 and G6

If you are using the Fluval G3 or Fluval G6 as a canister filter for your fish tank, then you may get the following error message on its LCD screen:

Alert!

Sensing air in the filter.

Motor will not operate.

Refer to instruction’s manual.

To see how you can potentially fix this issue, you can take a look at this troubleshooting article at Aquarium Blueprints.

Why the Fluval G3 and G6 is showing “sensing air in the filter”

The reason the LCD screen on your G3 or G6 is displaying the “sensing air in the filter” is due to the lack of water in the canister filter.

How to fix “sensing air in filter” issue for Fluval G3 and G6

In order to fix this air issue when using your Fluval G3 or Fluval G6, we recommend that you take the following steps:

1. To start off, unplug the canister filter from the power outlet.

2. You should make sure that hosing is securely sealed and plugged into the canister.

3. You should also make sure that the chemical filter cartridge and the mechanical filter cartridge are properly installed inside your G3 or G6.

4. Moreover, you may need to reposition your canister filter in relations to your fish tank.

The G3 and G6 work best if it is underneath the aquarium. However, make sure that it is no more than 4.9 feet underneath the tank.

5. For the hosing length, make sure you aren’t any hosing that is longer than 9.8 Feet. Furthermore, you should avoid using a different hosing type than the one that came with your filter as it may not work as effectively.

6. Furthermore, the bottom portion of the intake, which will pump water into your filter, should be completely underwater.

7. Once you are sure that your Fluval G3 or G6 has been set up correctly, you can then press the priming button all the way down several times to add water in your canister.

When priming, you may notice air bubbles coming out of the output nozzle of the filter. Keep pressing the priming button until you no longer see any air bubbles coming out of the nozzle, which signifies that there is no air present in your canister.

8. After fully filling your G3 or G6 with water, you can plug the filter back into the power outlet.

9. After plugging the canister filter back in, the LCD screen will turn on. The G3 or G6 should start pumping water in and out of the aquarium shortly afterwards.

If the canister isn’t pumping water, then you need to repeat these steps over again as air may still be present in your canister.

If you are still getting this error message, then we recommend contacting Fluval for additional help.