My question has to do with Cal-Hypo in the skimmer. I've seen mixed reviews on whether this is permissible or not. I don't have an Inline-chlorinater on the pool. My main concern is will this be okay for my DE Grids and heater etc, if I add cal-hypo to the skimmer when wanting to shock the pool. A friend of mine who has been doing service for 30 years said it's fine as long as the pump runs for at least a couple of hours after you administer it through the skimmer. Your feed back?