This bottle of reagent grade ammonium chloride is for use when fishless cycling.
Concentration is 40 mg/ml of total ammonia-nitrogen (TAN).
Dose 4 drops per gallon of aquarium water.* Use with One and Only Nitrifying Bacteria.
Generally during a fishless cycle you need to add ammonium chloride to your tank 3 times so:
a 2 ounce (60 ml) bottle will cycle 100 gallons (359 liters)
a 4 ounce (120 ml) bottle will cycle 200 gallons (757 liters)
Some conversions:
1 drop equals 0.05 ml
1 ml equals 20 drops
1 teaspoon equals about 5 ml which is 100 drops
1 tablespoon equals almost 15 ml which is 300 drops
