How to Set Up an Undergravel Filter

A filter can be the most essential piece of equipment in your aquarium, and undergravel filters seem to do this vital job well. They work by pulling water through a layer of gravel and a filter plate and trapping waste and algae there. Clean water from under the filter plate and gravel is then pumped up into an uplift tube and deposited back into the aquarium. It's important to make sure you have your undergravel filter set up and working correctly before you introduce your fish to the aquarium.

Things You'll Need

  • Undergravel filter
  • Uplift tubes
  • Uplift tube caps
  • Air pump
  • Gravel
  • Airline tubing
  • Carbon filter cartridge
  • Fish tank
  • Water
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Instructions

    • 1

      Place the filter plate section of the undergravel filter in the center of an empty fish tank.

    • 2

      Push the uplift tubes securely into their sockets.

    • 3

      Rinse the gravel thoroughly, cleaning it of any dirt or debris. Spread it in an even layer over the bottom of the tank and over the filter plate of the undergravel filter.

    • 4

      Connect one end of the airline tubing to the air nozzles on the filter plate or uplift tubes, depending on the filter model. Some models will also require that you run the airline tubing up through the uplift tubes.

    • 5

      Connect the other end of the tubing to the air pump. Place the air pump on an even surface outside the tank above the level of the water inside the tank in order to prevent the water from flowing backwards into the pump.

    • 6

      Plug or cap any uplift tubes that are not being used so that fish can't swim into them. When using an air pump, you'll generally need to use only two uplift tubes.

    • 7

      Pour water into the tank. Place a small saucer on the bottom of the tank and pour the water onto it to limit disturbing the gravel. Remove the saucer when finished.

    • 8

      Smooth over any unevenness in the gravel that may have occurred when pouring the water in, so that the undergravel filter will work efficiently.

    • 9

      Plug in the air pump and turn it on. Make sure that the filter starts running and pulling water though the system as it should.

    • 10

      Run the filter for at least two days before adding fish to the aquarium. This helps rid the water of any imperfections and guarantees that your undergravel filtration system is working correctly.