You should chock your pool once per week (we typically recommend at the end of the weekend after the pool gets its' heaviest usage). Shocking the pool should be done at night once the pool is no longer in use for the day. After shocking the pool keep the pump running over night to circulate the water. The shock will oxidize organic compounds (sweat, sun tan lotion, etc) out of the water to keep the water clear and shimmering. 1 gallon of liquid shock should be used per 10,000 gallons.