what GDP are you talking about? The pics in my album of the outdoor (its all outdoor in my album, all over a year old as well)? If that is what your talking about..... the end result had very little to do with ph, and a lot more to do with a 1/2 cu. ft air pocket under the huge "pot" it was in. But if you READ through the journal pertaining to it, you would already know that...... lol.....
Obviously, I stated I know my water well, and am well practiced. I also stated that I still have additives were I too need to use them. I have been speaking purely of my growing experience.
I have not suggested that Drella do anything at all. I have made an example out of my observations and experiences, as well as commented on what I have seen from other people. I have also pointed out that I checked EC, TDS, ph, etc. up until I felt comfortable not using them anymore..... I still occasionally break out a meter just to make sure..... me, not drella, I can't comment or speculate on what I have such little knowledge about (HIS grow). I offer relative experience and points of view.
so what would I have drella do? Nothing. he does whatever he wants. What I can do though, is explain my experiences etc.
Your comments have been nothing short of insulting, arrogant, and incendiary.
Obviously Drella has learned a lot on his own from my mention of my experiences. The only advice I really have to offer is "it all depends, and its all up to you".
You really want to help him Understand what he's doing..... throw some links up to back up your theories and concepts. Let him explore the sciences etc. involved so he can make up his own damn mind. And putting nute solutions in soils.... depending on the soil, but quite a few of the most popular ones, the ph does go up as water and nutrients are absorbed by the plant, as well as it interacting with the additives such as OISTER SHELL or DOLOMITE LIME etc. etc. that are premixed into the soils (they are called ph adjusters) EC does not directly reflect TDS and vice a vers, which is precisely why there are the two separate measurements you can take.
http://www.tdsmeter.com/what-is?id=0019
http://www.firstrays.com/tds_and_ec.htm
pay close attention, be sure you understand the material being reviewed.
And I am pretty sure he said he was growing in sunshine aggregate soiless mix. Using a completely different nutrient line up than myself.