Subbed and along for the ride. This is very similar to what I am doing, so it's good to see how they progress. I just got the big bag of Roots Organic, 2CF Perlite, and 30lb Worm Castings. I also have big bag of peat moss. I am trying to decide how much peat moss, perlite and worm castings to add into the RO soil to kind of mimic a light warrior seedling mix for my babies. The hydro store was completely out of Fox Forest soils, but I was super stoked that I got the last bag of the RO soil. I know it is a hot mix, so I am thinking it needs to be diluted a little, or at least put down at the bottom of the pot with a lighter mix up top. The hydro store also had a pH/light meter/soil moisture probe for like $10, so I guess I got lucky there.
Just FYI, from research I did in my aquarium days, I think you cannot really pH test distilled water (same should be true for zero TDS RO/DI and rain water). The reason being, is there are absolutely no ions in the water, so you can get test results ranging from 5 to 8 and it is all bogus. Distilled water, by definition is pure and neutral on the pH. Hope that helps.
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