I go to Walmart and buy Walmart Great Value Purified Drinking Water - No Minerals added - for $.60/gallon. They use multiple processes to filter including RO, Ultraviolet Light, Micron Filtration, and Ozonation. I can't remember exactly what the PH was out of the jug, my recollection was 6.1 to 6.4. My guy at the local hydroponics store suggested using the Walmart Great Value Purified Drinking Water - Minerals added - $0.60/gallon instead of the no mineral water. He stated that might be adding to the Cal/Mag problems I have been experiencing. Just got back from local Walmart and could not find their brand of GVPDW - MA, so I bought Nestle's Brand Purified Water with added minerals - $1/gallon. I will use that until the end of this grow. As for the organic ferts, Yes I just started the Roots Uprising Foundation and Uprising Bloom to help get my Double Grapes to the finish line. Still to early to tell just how effective the Organic Roots Uprising fertilizers have been, but it "seems" as though the yellowing has not gotten worse in the last 4-5 days.
My journal for the Double Grape is at
https://www.autoflower.org/threads/...o-double-grape-in-soil-with-gbd-ss-mix.64084/