I personally had a few ph issues with my promix. I had to flush the plants every two to three weeks which was a little bit to early for what I thought. I would add some lime to the promix If i use it again. I heard Sunshine Mix 5 is almost the same as promix just has a slight advantage when it comes down to PH buffers. I had a 50/50 mixture with perlite making flushing them a breeze:hippy:
Not to mention beautiful root structures.