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How to drain water from the Fluval FX4 and FX6 canister filters

The Fluval FX4 is designed for fish tanks that can hold up to 250 gallons or 1,000 liters. The Fluval FX6 is made for bigger aquariums that can hold up to 500 gallons or 1,500 liters.

Both of these big filters come with a utility valve to quickly drain water from the bottom of the canister. To find out how you can properly use this valve, you can take a look at this step-by-step tutorial at Aquarium Blueprints.

Why you should use the Fluval FX4 and FX6 utility valve

The Fluval FX4 has a filtration volume of 3.7 gallons or 14 liters while the Fluval FX6 has an even bigger filtration volume at 5.28 gallons or 20 liters.

When both of these canisters are filled with water, they will become quite heavy to carry around for maintenance.

By using the utility valve, you can easily remove the water from within the canister without having to do any heavy lifting. Otherwise, you will need to carry the water-filled canister, remove the filter media and then carefully pour out the water from the top.

How to drain water from the FX4 and FX6

In order to drain water from your Fluval FX4 or Fluval FX6, we recommend that you take the following steps:

1. To begin, make sure that the red dial next to the utility valve has been set in the vertical position, which indicates that it is currently closed.

2. Turn the lock nut on the utility valve clockwise in order to loosen the rubber cap.

3. Remove the rubber cap that is plugged into the utility valve.

4. Plug the utility valve hosing, which should have been included with your FX4 or FX6, into the utility valve.

5. With the hosing plugged into the utility valve, turn the lock nut clockwise to hold the hosing in place.

6. Place the other end of the hosing on a water bucket, water container or drain. If you are using a bucket or container, make sure that it is placed below the canister to make the draining process more efficient.

7. Turn the red dial on the “IN” valve fully horizontal to prevent water from being pumped into the filter.

8. You then need to turn the red dial on the “Out” valve fully horizontal to prevent the water from being pumped out of the filter.

9. Unplug your Fluval canister filter from the power outlet.

10. Turn the red dial on the utility valve counterclockwise into the fully horizontal position. Water from the FX4 or FX6 canister should start flowing out.

11. Disconnect the “OUT” valve from the canister filter.

12. If you are using a small bucket or container to hold the water you are draining from the canister, then you can turn the red dial on the utility valve back to the vertical position to close the drainage before the bucket or container overflows.

Afterwards, you can empty out the bucket or container and then use it again to store more out of outgoing water from the canister by turning the red dial on the utility valve back to the horizontal position.

13. Once you are done with draining water out of your Fluval FX4 or FX6 canister filter, make sure to set the red dial on the utility valve back to the fully vertical position to prevent any accidentally drainage or leakage.

Afterwards, you can remove the utility valve hosing and then reinsert the rubber cap into the utility valve.

You can also leave the utility valve hosing plugged in to the valve and then place the hosing on the hosing clips located at the top of these canister filters.