I know that usually one is advised NOT to mix concentrated chemicals together before adding to the pool. However, I remember reading (on this forum) about a product that contains both borax and dry acid. I believe it's Proteam Supreme or something in the Proteam line.
Would it be a bad idea to formulate this sort of thing myself, for adding borax to my spa? I believe I calculated about 13 oz of dry acid per lb of borax. . . I added them separately the last time around, but it would certainly be convenient to have the two products in one. The cautions about mixing chemicals are well drummed into my head, so I thought it would be prudent to ask first.