It slipped my mind a while back, but something like a 10% over feed can reduce yields 20%. Or perhaps it's the other way around. All I committed to memory is that any sign of over feed means dropping the EC. There is no gain from 'just a bit' and the loss from under feeding is less pronounced. I could expand on that idea, saying the plant can get more food by opening the stomata, which harvests more co2 too. While an over feed does the opposite. I'm not really sure though. I just know that even mild over feeding is bad.
What is over feeding... well that's another question. To me, it's any hint of tip burn. Then back off 10% to stop the burn, and 10% more to get them drinking and breathing. Which under LED is even more important, for that Calcium uptake.
It slipped my mind a while back, but something like a 10% over feed can reduce yields 20%. Or perhaps it's the other way around. All I committed to memory is that any sign of over feed means dropping the EC. There is no gain from 'just a bit' and the loss from under feeding is less pronounced. I could expand on that idea, saying the plant can get more food by opening the stomata, which harvests more co2 too. While an over feed does the opposite. I'm not really sure though. I just know that even mild over feeding is bad.
What is over feeding... well that's another question. To me, it's any hint of tip burn. Then back off 10% to stop the burn, and 10% more to get them drinking and breathing. Which under LED is even more important, for that Calcium uptake.
This is response to question about PAR from someone growing GG4 for several years -
I try to stay about 8 900 on my tops under led. Usually my nutrients or heat give me foxtailing...
I knew it could not be the light strength, since so weak, and knowing above 650 PPM was a severe negative in growing GG4. Was not sure why, but heard many times it would screw up grow.