I run 4 ebb and flow trays (homeade for $65ea including hydroton,pumps,timer ect..) that are about 36"x24", in my flower room. I run 2 sets, 4 wks apart. Even tho i quit using enhancers, I'm fairly certain I would lose a lot of yield and quality if I didnt up the ppms a tad as they got bigger. Week1 of flower is usually 350ppm, while week 6 hits about 850. Im thinking that trying to get a one size fits all nutes may work, but youd miss out on the very reason we grow hydroponically. You know, to get the most out of your gals. Besides, why starve your huge buds, or risk burnin' your young? Maybe its even simpler than that tho.
I do a perpetual grow for my mothers of random strain, in a smaller cabinet. Now, those ladies get the same solution forever! I have it set at about 120ppms, and under 100w hps, they love it. Biggest worry is that if you get enough nutes to sustain any serious fast growth, you may burn young things. Probably depends a lot on your lighting and growth rate too. Bast of luck to ya