Just watered plant and took PH reading of run off. Growing in FFOF soil. Going in water registered in the low 6 range (6.2's) and run off was in the high 6 range (6.8's). I use drops so range is a quessestimate. I did add silica but adjusted PH before watering. PH is within acceptable range but should I be concerned with so much of a jump in PH runoff?