BEGINNER: Use 1 capful (5 mL) for every 200 L (50 gallons*) daily or as needed to reduce ammonia. (Note: The 2 & 4 L container’s cap is 10 mL). ADVANCED: If you have an Ammonia Alert™ that is reading alert, then use 1 capful (5 mL) for every 400 L (100 gallons*) daily. If it reads alarm, then use 1 capful for every 200 L (50 gallons*) daily. If it reads toxic, then use 1 capful for every 80 L (20 gallons*) daily. EXPERT: If using our MultiTest™: Free & Total Ammonia test kit, use 1 capful (5 mL) for every 40 L (10 gallons*) to remove 1 mg/L (ppm) of free ammonia. Alternatively you may employ the following formula for a variety of ammonia and water levels: 0.125AV=m (for volume in liters) or 0.5AV=m (for volume in gallons*). A=ammonia concentration in mg/L, V=the volume of water being treated and m=the volume of AmGuard™ to use in mL. For example, to remove 1 mg/L of ammonia in 100 gallons* you would use 0.5*1*100=50 mL. If water temperature is above 30 °C (86 °F) do not use.