I figure what is causing the rise in ph is your nutrients, but don't get to hooked up on it. There is a large spectrum of ph levels that a plant will grow perfectly healthy. The "ideal ph" that everyone aims for is actually to prevent disease not yield bigger plants.

Don't worry about losing a few roots, it will cause a little stress on the plant and nothing more. Actually, I find the plants I abuse the most give me the best weed (don't start torturing your plants though). As for root juice, I don't know what that is exactly, but I would not add it until your plants are back to their perky selves. I find a little fresh water will do wonders, then go to work feeding them.

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