Nice setup man. I'm rocking some Mars lights and tent too, quite happy with them! You just wait, there's 2 or 3 weeks of stretch left for that girl lol. I hear ya about the humidity too, with things warming up I'm finally able to keep it around 50% but running 2 humidifiers lol. With your water, I would only adjust the pH when you are ready to use it. The way the guys at the grow store explained it to me was if you bump it up, it will slowly fall back down, giving the plant a range to access nutrients. Vice versa if you bump down. I believe there is also salts or something that can build up from the pH adjusters if say you don't use a whole jug so you bump it up again next watering. Hope that helps man. Happy growing!