Instant Fresh Toilet Treatment is a simple, one-step, highly effective way to deal with the boat&';s holding tank. Eliminating the need for multiple chemicals, this efficient, biodegradable formula quickly breaks down waste to remove potential odors, while leaving a light, pleasant scent behind. Special additional lubricants prevent your drain valves from sticking and is safe to use in portable loo&';s, on your boat, or in your RV. 16 fl. oz Non-formaldehyde formula Non-staining Biodegradable Latest technological lubricants keep drain valves from sticking Breaks down waste quickly and efficiently One ounce treats five gallons Fresh lemon scent controls holding tank odors Complies with EU criteria for biodegradable products Treats up to 303 liters or 80 Gallons total Directions: Holding Tank Systems with BLACK WATER:Add 30 ml for each 19 liters of tank capacity. Pour through toilet into holding tank and add 4 liters of water. Hot weather and long retention times, may require additional treatment. Holding Tank Systems with GREY WATER:Use 30 ml for each 38 liters of tank capacity. Pour through shower or sink drain and add 4 liters of water RECIRCULATION TOILETS:Pour 236 ml into initial water charge. PORTABLE TOILETS:Pour 118 ml into waste holding tank and add water to cover tank bottom