How long after shock treatment until we can swim in our pool?

Allow enough time for the pump to circulate every gallon of water one time. Number of gallons in pool divided by GPM will give you number of minutes divide by 60. This equals the time you need to wait to swim safely. Allow enough time for the pump to circulate every gallon of water one time. Number of gallons in pool divided by GPM will give you number of minutes divide by 60. This equals the time you need to wait to swim safely.