I would suggest a 10% weekly or 20% every other week schedule for PWC
's. Some do more, many do less, but there's no denyng the benefit of a PWC
So think about upping your weekly schedule to 10 gallons. Pick up a 20 gallon Brute (by Rubbermaid) trash can to mix the water.
But first, what are you using for source water? Tap?
unit will strip all buffering capacity out of the water as well as most everything else. Then your salt mix should get you to the ~8.2 range.