I don't think it is quite the same thing Reef Primer is "potassium salts" but its different from potassium chloride. I find potassium chloride is much harsher on the corals and makes them slime up more.Sadly, I believe you are correct. This was my experience as well -- although I dipped with food grade potassium chloride @ 1 tbls per gallon. Since the active ingredient in Reef Primer is "potassium salts" I feel like they might be the same thing.
Annoying and tedious work, but effective.
If you follow the method I suggested the AEFW is quite easy to beat.