
lots of great input my fellow gellies!

I'm going to school on this as well,... so many problems show up in the Infirmary with pH, and many with AN or other self-adjusting pH nute's, it has begged the question: just how much buffering capacity do they have? Is it mainly referring to just what the nute's do in solution only-? I believe it does,... for soil/coco growers in particular, maybe hydro to a lesser degree(?), there's the dynamics of what the plant and the microbes do with pH as well, and this is where the other part of the "equation" can go wrong.... my first thoughts are what the difference is between using RO/Di (any source of low to no hardness water) vs tap, and that is the degree of hardness in the tap water, i.e., buffering capacity... the nute's want to adjust to mild acidity, right? In RO water, there's no buffering, so even tiny inputs can have potentially large pH swings; in tap, the hardness is variable, so must be measured by EC or ppm's at least to get an idea of just how hard it is,.. the more loaded with buffering minerals it is, the more the "built in" buffers of the nute's have to work to drag the pH down to the acidic range; in other words, the harder it is, the more depleted the buffering chemistry becomes, so by the time it goes into the res'/coco, it's might already be partly or totally depleted of this buffering capacity, and can't help regulate much, in any, further,... in RO, this doesn't happen; there's still untapped buffering capacity by the time it goes in there, and so can help continue to regulate pH to some degree,... I'm guessing this is one reason why AN says to use RO/Di water.... another reason might be dependent on if you use coco specific nutes, or non-coco types... the chemistry is different, I think largely having to do with dealing with coco's peculiar CEC involving Ca, Mg, and K.... I'm wondering if you use coco specific nutes, additional Ca-Mg is unnecessary (at least initially), and if you do, to what degree will it mess with the buffering, since most all Ca-Mg products are at least in part, if not totally, carbonate based, which does add buffering minerals,...
...I'm curious to what
Hans, FI, WEP and others use for water, and if they use Ca-Mg... if they use tap, RO, or make a blend, what the ppm's are before adding anything,...
A-Train, will you be going full RO type water? it might make most of by brain-farting lecture moot-

- and I hope I didn't just poo-the-water by reducing clarity in your water question!

.......As for Si, it'll add ppms, but since it's just Potassium silicate, it doesn't contribute to any buffering... however, Si is a
fantastic element, with several key benefits! To not use it is foolish, IMO... If you've not read this yet, here's a great article on Si- (
http://www.cannabis.info/gb/abc/10005474-the-marvels-of-silicon&hloc=1 )
**** EDIT-- Waira's mug was in the Pipe about the Si product (not AN's at least, clearly!)-- it can raise pH substantially

--not a buffering contributor per se, but can swing water/nute's soln. toward alkaline!