Dose 4 drop per gallon of aquarium water.1 drop equals 0.05 ml so this bottle will treat a total 1,180 gallons.Generally during a fishless cycle one needs to add ammonium chloride to their tank 3 or 4 times so this bottle is enough ammonia to cycle aquariums up to 150 gallons.Some conversions:1 teaspoon equals about 5 ml which is 100 drops.1 tablespoon equals almost 15 ml which is 300 drops