I received my advanced nutrients ph down tonight. I am on day 30 of my first grow. I have been using vinegar to ph down my water after nutes. My tap water is 8.4. I did a test and added 1 ml of ph adv nutes down to 1 gallon of tap water and my water tested at 3.1. I ended up figuring out that .3 ml will drop it 2 ph points. Is this the same experience that everyone else has had? If so I am thinking that I am pretty good on ph down with this gallon for the rest of my life.