in other mediums there's a lag/disconnect between your feeding and the plants uptake. varies by each one of course. in a healthy DWC your nutrient profile is, for the most part, entirely available to the plants as-is. running simultaneously low overall PPMs + boosters, you run the risk of skewing your profile. with a dialed environment & lots of water uptake, they're gonna show problems especially with excesses. (i feel) they do require extra P/K at the different stages in flower but i really think it's a fine line.
here's what i did. downloaded cannastats, plugged in the other stuff i was using (it comes pre-loaded with GH 3part) and started running different numbers. i don't know what the ideal profile is but 4-3-3-9 cm-m-g-b works great for most strains. start to finish. so i use that as my baseline. i went thru all of my various crusty logs of my mixes that i've kept over the years and... wow. huge numbers especially P & K. for reference, FooDoo's 2.5/2.5/7.5 mix comes out to
60-43-99-41-40-56 N-P-K-Mg-S-Ca, which in a dialed environment is gonna kill it, start to finish, with most (but not all) strains. no boosters, sugars, organics, nothing else. every shorter, leafier, indica-leaning strain i've got thrives with it. my issue is that i like to run GG4, an absolutely exceptional grower in terms of stretch, well-spaced budsites, its ability to fill out the canopy on its own, etc.. and either wants lower humidity, more stripping/fan & inferior budsite removal, or more.... P??? about ready to just run other strains because they're all turning out awesome, just less yield and more canopy work. with GG4, little work is required to get a somewhat consistent & chunky overall appearance to the pack.
last run, i had a much shorter, lower yielding mostly GG crop that i used no boosters on and was lacking in the velvet-y texture & swollen calyxes only on the very tops/most well lit portions. most of the very top buds were not as swollen as the stuff that was getting less light. my thinking was deficiency over toxicity and thought more frequent nute changeouts would help keep things in check. but this still didn't help on my latest round. last crop was tiny but still got a 70% yield. unfortunately i'm in the process of trimming another underwhelming GG4 monocrop that will have good weight and good potency by local standards, but is still lacking in density & the swollen calyx factor that i had when i had vented, mostly uncontrolled climate rooms and ran 2.0+ EC. even though i kept the canopy leaf/bud temps under 80, the whole top is covered with bleached foxtails that are actually dense, sticky and dank and have the texture that i wish all of the other top bud had. great uncured smoked! the bleaching is because of short ceilings and being 1' or less from the glass. but the real oddity is how these foxtails turn out with the proper texture, smell, swollen trichome head coverage, etc...vs. all of the buds right below. just white as can be.
my point of sharing this is..a) don't necessarily just follow tips from others, to some extent you have to, but assuming you have a baseline that is working OK, don't go too far off of that. b) maybe someone has some thoughts on my issues? i ran about 1-2 p:k except for a stretch near the end where it was evened up. the more intense the lighting, the worse affected the buds seem to be. new hoods added yield but more imperfect tops. mid-light stuff is turning out the best with these overgrown crops, but lacks the density & weight that the top stuff should have. reading points to lack of P.
tbone.. i admire & envy the system but dont envy your role as being the one who has to tune that in! what are your symptoms for too much calcium?