Quote Originally Posted by Rusty Trichome
Coco tends to retain mineral salts, so you might need an extra flush or two during the plant's lifetime.

I use Fox Farms nutes, and follow their weekly schedule pretty closely. But living in the desert, it get's pretty hot which adds to the stress of giving full strength nutes. To compensate, I cut the dilution in half, but feed twice weekly. Same weekly totals overall with less stress to the plants. Plain, properly ph'd water in between if necessary. I use phDown (phosphoric acid) to adjust my 8.0 wellwater down to 6.8ish. My half-strength nutes bring it down to 6.3ish.

If you have to dick with soil ph to compensate for water ph, something is going wrong. If you are adjusting water with ammendment solutions to bring the ph into line, something will likely go wrong like excessive vitamins or excessive hormones/nitrogen (root stim)

What are you using to check ph, and when was it last calibrated? Could it be a simple mis-reading?
I agree, however, each amendment sends the pH in a different direction and at a diff rate. In 1/2 gal; It takes me 28 drops of pHU to get my ferts from 5.4 -6.5: it takes 1/8tsp root stim to do the same thing so i switch between amendmente every feeding and watering. H2O requires lowering pH from 7.6+ so i'll use pHd or CalMag. The Ph+ and pH- solutions which, IMHO, do just as much to harm a plant if overused, and, used as the sole means of pH adjustment when pH is not within .2-.3 of target. I have to go almost 1 point. 45dps pHd per gal to 6.5