I did a fresh fill for my spa and I'm using the BBB method (first time).
So far, so good. However I do have a question about the use of Borax. I am assuming that on a fresh fill, the level is "0". I also have no way of testing the Borate level with my test kit. So, according to the pool calculator, I need to add 551 grams of Borax, followed by PH down (dry acid) in the amount of 352 grams. I've searched for measurement specs for Borax relative to grams per cup. I found one answer on the web that indicated 1 cup of Borax = 204 grams. That would mean I would require 2.7 cups of Borax to attain 50ppm for my 1,250 liter spa. Would that be correct? It just sounds like a lot of Borax.