well u got the pictures and results up there :) so far no heat issues and they are a bargain I think for their price...I'm doing hydro bubblers, next grow I will aim at using aeroponics technique to increase my yield
I'm not saying to stop feeding them. He should take into account how much he feeds them. Add nutes to that 0 ppm water and feed accordingly. Since it is in soil I would also suggest at keeping your ph at 7. And even if he does use 0 ppm water and adds nutes he should keep the nute strength low...
I understand what your saying but even tap water has ppms. Depending on where you live the ppms maybe higher or lower. I suggest getting r/o water with 0 ppms and adgjusting from there. As you said...however the plant directs you.
Nute burning is due to overfeeding it with nutrients. Keep in mind that water has a tds or ppm, meaning your feeding it nutes. So why would you keep feeding it?