How to Cancel Out Ammonia in Water

Ammonia consists of hydrogen and nitrogen atoms. This chemical compound exists in aquarium water as either free ammonia (NH3) or as the ammonium ion (NH4+). The form that ammonia takes determines its toxicity in the aquarium. Free ammonia is highly toxic and will kill your fish. The toxicity of this form of ammonia is exaggerated with an increase in pH and temperature. The ammonia reading in any aquarium should always be zero, which is easy to achieve if you follow a few basic husbandry steps.

Things You'll Need

  • Aquarium chlorine and chloramine neutralizer
  • Dip-and-read ammonia test kit
  • External filter (hang-on or canister)
  • Biological filter material (bio balls or similar)
  • Mechanical filter material (floss or filter pads)
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Instructions

    • 1

      Treat all top-up aquarium water with an aquarium chlorine and chloramine neutralizer. Add 1 tsp. of chlorine and chloramine neutralizer per gallon of water. Add neutralizer when setting up a new aquarium as well.

    • 2

      Use a dip-and-read ammonia test kit to test for the presence of ammonia in the aquarium water. Follow the instructions included with the kit to obtain the correct readings.

    • 3

      Ensure that your hang-on or canister filter has a biological filter compartment. Fill this compartment with bio balls or similar highly porous biological-filter material. Huge cultures of beneficial bacteria will colonize this material and will convert the ammonia to harmless products.

    • 4

      Place filter floss or filter pads between the incoming aquarium water and the biological compartment to make sure that large pieces of dirt and detritus are physically trapped before they smother the bacteria on the biological material. Rinse or replace this mechanical filter material on a regular basis. Check the condition of the floss or pads on a weekly basis if the aquarium is overstocked.

    • 5

      Remove a number of fish if the aquarium is heavily overstocked. Hobbyists tend to add extra food to overstocked aquariums and uneaten food causes ammonia spikes in the water.

    • 6

      Vacuum the gravel once it is visibly dirty as organic waste matter from your fish will accumulate between the individual sand grains. This metabolic waste contains ammonia.

    • 7

      Remove any dead leaves from aquatic plants and the carcasses of dead fish as soon as possible.