How to Replace a Carbon Filter in Fish Tank

Replacing a carbon filter in a fish tank is easy. It is something that should be done on a monthly basis, more often if the tank is very populated or heavily planted. There are no tools required, just a few items to keep things neat and a source of fresh water.

Things You'll Need

  • Carbon filter with old cartridge
  • New carbon filter cartridge
  • Small bucket
  • Fresh water
  • Activated charcoal, also called carbon
  • Small paper cup or drinking glass
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Instructions

    • 1

      Unplug filter from electrical outlet. Remove top of filter. Slide out carbon filter cartridge.

    • 2

      Place carbon filter cartridge in the bucket. Bring to sink or other source of fresh running water.

    • 3

      If the cartridge is disposable; remove the plastic tab from the top of the cartridge and save it. Hold cartridge over a garbage bag and pull cartridge frame out of filter material. Save the frame. Rinse everything with warm water.

    • 4

      For refillable cartridges, open filter cartridge. It should open like a door. Empty contents into the garbage. Rinse cartridge with warm water.

    • 5

      Place the frame for a refillable cartridge into a new filter medium. Add charcoal packet or a tablespoon of activated charcoal. Replace plastic clip. Add enough activated charcoal to fill the sectioned areas of the refillable filter. Close door to filter cartridge.

    • 6

      Rinse the new or refilled cartridge filter under fresh room temperature water until the water runs clear and no charcoal dust leaches out.

    • 7

      Replace filter cartridge into the filter unit. Plug into electrical outlet. The filter should automatically prime and start to run. If it does not prime, use the cup to add water from the fish tank into the filter until the filter runs on its own.