I have to get a PH pen too... do you have a recommendation for me perhaps? I like the look of those jiffy peats. I saw some at my supplier the other day and was in two minds about getting some. I want to take some cuts so I think I should get some next time. I like your scientific method and your plants look good. I love purple haze! I am quite jealousOh I didn't think of that. Is or better than vinegar? Vinegar is only needed in very small amounts though as my first batch dropped to 3.9 hahaha