How to Lower Freshwater Ammonia

Fish need a certain environment to thrive, but new freshwater tanks often have large amounts of ammonia in them. Overfeeding fish can also cause the ammonia levels to rise to the point where the fish are put in danger. Some quick fixes can temporarily remove the ammonia from your freshwater tank, but in the long term, you will want to build up a natural biological filter that will nitrify ammonia. Then you won̵7;t have to constantly manage the ammonia levels.

Things You'll Need

  • Chlorine/ammonia removers
  • Deionizer
  • Filter
  • Zeolite
  • Sodium salicylate ammonia test kit
  • Enzymes
  • Nitrifying bacteria culture
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Instructions

    • 1

      Replace part of the old water with new water that has been purified with reverse osmosis or deionization. Since city water can contain ammonia, add chlorine/ammonia removers at twice the recommended dose to thoroughly eliminate the ammonia.

    • 2

      Add zeolite to the filter. Zeolite is an ammonia-removing resin that is porous, but remains rigid in water. Different zeolite products have different recommended measurements, so check the instructions for the correct amount to use.

    • 3

      Use a sodium salicylate ammonia test kit to determine how much ammonia is in the tank. Most kits have you fill a test tube with water, add ammonia test solution, shake the test tube for five seconds, wait five minutes for a color to develop, and then compare the color to an ammonia test color chart.

    • 4

      Add enzymes and nitrifying bacteria cultures to the freshwater tank to speed up the buildup of these bacteria. This step is not completely necessary, since the bacteria will build up on their own. However, stressed fish have a harder time surviving.

    • 5

      Reduce the amount of waste produced in the freshwater tank to prevent ammonia from building up. The most common reason for ammonia buildup is overfeeding. Some people are worried about fish starving if they do not receive enough food, but most fish can miss some meals without being harmed.