Don't know about that brand, but you want to check your nute pH every time regardless in my opinion. If you are using tap water (sorry, haven't rescanned the thread) or even purified water, the pH is bound to be off from the beginning. I was using my tap water and found out it was around 8.5, then switched to purified water from the store, but it is still neutral pH 7. Once I add my nutes I have to add tons of pH down to get to 5.5 - 6.0.
What are you going to do about the mites? I had them last go round and took care of them with some pyrithrin spray that said safe to use up until harvest and was made for fruits, veg's and herbs. It basically fried my pistils, but I kept the mites under control. I say under control because I never totally got rid of them, but I didn't have any web issues and stopped spraying 2 weeks before harvest.