ok.. here's what I got

Tap water ph: 7.4

soil run off of promix in a 4" pot: 7.4


I used about 12oz of water.

so I would say that promix has a ph of 7. If you get some ph down solution and just ph your water to 6.3-6.8 you should be just fine I think.

Thinking back on it that's what I did initially before I transplanted them.

I hope this helps.