I have ran some at 1400 ppm & they just can't get enough with their leaves just barely turning down then have had some that just bend and sag until you have to back off a couple of hundred ppm. After talking with some subject matter experts… I try to keep my pH @ 5.2 - 5.5 during rooting the 1st wk. I use APS (& rooting solution) and the pH is down around 5.0 for either cloning or seedling keeping the ppm count below 300 ppm. You’ll see a lot of new growth after a few days. Then stop the rooting or they will bush up like all hell. Just bring up the nutes a little each week. 300…400...500… Typically I run my vege nutes early at 800 ppm but always hit them with auxiliary supplements that drive the nute count up to 1000–1200 ppm until I flush and start over. And with evaporation and the plants uptake, 2 farms can take close to 2 gals/days. The ppm count goes up as water evaporates or is used. Top off with straight water after adj Ψ (if you have a reservoir then make your adj accordingly. Probably won’t have to…it will read about 700-800 after dumping 300 ppm pH adj, Calcium adj, Anything else adj tap water. When they are feeding, it doesn’t take much to drive the count up and pH up. I generally add Calcium to the water here since it is so soft. Takes about a tblspn per 6 gal to get the ppm count up to 300 ppm. Helps with the Nitrogen uptake. Typically I run my nutes in early bloom at 1000 ppm but always hit them with auxiliary supplements that drive the nute count up to 1200–1400 ppm until I flush and start over. Same kinda thing. Hit them with some bud blaster the 1st week and then again the 2nd to the last week supplementing with Booster all along the bloom cycle with the normal bloom nutes after they have settled in and are drinking hard. What are anyone’s opinion about the size and quality of bud running nutes at 1000 ppm vs. 1200-1400 ppm. Unless you’re growing the same strain how do you know what’s best. I have had better luck – taste-wise and potency-wise running at 1000 ppm. Cheaper too. For light…. 2 ea Sun 125 w Growlight (Vege bulb 2700) for clones, 1 ea 400 MH w /2 ea Sun 125 w Grow for vege and 1000 HPS for bloom…
Ψ - The Adj (prepping water for nutes) – B1 ThriveALive, SM-90, Prosilex, Calcium, pH Correction, Super Oxy H2O2, etc.
I am in total agreement with caliorbust about pH count being so important...
Monty