How to Get More Oxygen in a Fish Tank

Aquariums require high enough levels of dissolved oxygen (DO) for healthy fish; DO levels are determined by water temperature, salinity and atmospheric pressure. You can control water temperature and salinity, and with the addition of an aeration system, you can increase a tank's DO. Aquatic plants also increase DO, but the simplest way is to add an aeration system and monitor a tank's salinity. Avoiding overstocking your aquarium with fish and overfeeding your fish are other important steps to increasing DO.

Things You'll Need

  • Air stone
  • Aquarium hose
  • Aquarium air pump
  • Salinity meter
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Instructions

    • 1

      Attach the air stone to the aquarium hose, and then attach the aquarium hose to the air pump. You can attach a series of air stones on a single pump with a splitter and attach valves to change the pressure on each hose. Longer air hoses are great for longer tanks.

    • 2

      Bury the air stone in the substrate of the aquarium, and run the hose through the top of the aquarium. You can build attractive seascapes using circular air stones.

    • 3

      Turn on the pump; air bubbles should flow out of the substrate. If there's no activity, check the hose for kinks. Smaller bubbles that take longer to float to the surface are better for a tank's oxygen levels.

    • 4

      Install the salinity meter in the aquarium according to the manufacturer's directions. If you're running a freshwater tank and the salinity is higher than normal, do a water change. If it's a salt water tank, verify that the salinity is appropriate for your fish. Higher salinity levels decrease a tank's levels of dissolved oxygen.