1) Remove all water from tank and system by turning on water pump, opening tank drain valves and opening all faucets and shower heads. 2) After system has fully drained, turn off water pump, close all valves and faucets and shower heads. 3) Add fresh water to tank to fill it approximately 1/2 full. 4) Add appropriate amount of AQUA Water Tank & System Flush required for full tank capacity (1 gallon for each 100 gallons of tank capacity). 5) Add fresh water until tank is full. 6) Move boat or RV several times in order to disperse Water Tank & System Flush throughout water. 7) Turn on water pump and open all faucets and shower heads, keeping them open and flowing for about 3 minutes. 8) Close all faucets and shower heads and turn off water pump. 9) Allow the treated water to remain in the system for approximately 30 minutes, then turn on the water pump and open all fixtures, allowing them to flow freely for about 3 minutes before closing them and turning off the water pump. 10) Open the tank drain valves to completely drain the tank, which will now be clean and deodorized. 11) Close the valve and fill the tank with fresh water. 12) Turn on water pump and open all water fixtures to allow water to flow freely for a few minutes to remove Water Tank & System Flush from water lines. To prevent water from picking up taste or smell from tank walls or pipes, use AQUA Water System Conditioner. To maintain water quality, treat it with AQUA Water Treatment & Freshener every time you add water to the tank.