Ammonium Chloride

  • Pure, dry ammonium chloride for use during fishless cycling
  • Ammonium chloride makes fishless cycling easy and establishes aquarium biological filtration
  • 1 tsp (4.5gm) per 100 gallons of water brings ammonia concentration to 4pp
  • Does not contain scents or other dangerous additives.

About Ammonium Chloride

In most aquariums, the biological cycle is started by introducing fish into the aquarium. The fish excrete ammonia, which acts as a food source for nitrifying bacteria. Nitrifying bacteria convert ammonia into nitrite and then nitrite into nitrate. Fritz Ammonium Chloride (NH4Cl) can be used as a source of ammonia to initiate the growth of nitrifying bacteria without the presence of animal life. Fish should not be present while using ammonium chloride.

Directions & Dosage

Aquarium ammonia concentration should be raised to 3-4 ppm before adding a source of nitrifying bacteria such as FritzZyme® or FritzZyme® TurboStart.

Be careful not to use too much ammonium chloride. Raising ammonia levels above 5.0ppm may actually slow the cycle time.

One level teaspoon of ammonium chloride is approximately 4.5 grams; 4.5 grams per 100 gallons of aquarium water will create an ammonia concentration of approximately 4 ppm. Continue to monitor both ammonia and nitrite levels. Do not reapply ammonium chloride or add fish until both ammonia and nitrite levels are at or near zero concentration. Once ammonia and nitrite concentrations are at zero, you should either add a second dosage of ammonium chloride or add fish so as not to interrupt the food source of your biological filter for more than 72 hours (3 days).

Safety Data: Keep out of reach of children!


Size Treats Item Number
500 g varies 89500



See below for frequently asked questions regarding Ammonium Chloride.

  • Ammonium Chloride Best Practices
    • Use along with nitrifying bacteria (FritzZyme or TurboStart) as a food source
    • No equipment restrictions necessary
    • Contraindications: do not add Ammonium Chloride to an aquarium with livestock present
    • Dry products measured by volume (teaspoons, cups, etc) will always give approximate results - use a gram scale if available. If a gram scale is not available, be sure to test for correct concentration after use and observe for any changes in fish behavior.
    • Overdosed? Perform small water changes if needed to dilute
    • Test with an ammonia test kit with a range up to at least 4 ppm

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