I just went through this and if you care to have a look at my threads about my experience you will see that by letting my temps rise my roots suffered and died. I actually lowered the EC and ran hydroguard and, most importantly, lowered the temps. The plants recovered and flourished. Is it possible they're underfed? Yes it is but I believe from my experience that his big issue was lack of DO first and for most. This run I'm doing is running at 500ppm at start and by the end of the week 300 and they are thriving. To say that his plants ended up with those roots by underfeeding is not anything I have experienced. Not arguing btw just relaying my experiences dealing with unchilled flooded root systems, which IMO are not going to allow plants to thrive.
View attachment 3936744 Try to ignore the color, Don't use myco madness, it turns the water black and the roots lol.
View attachment 3936745
The format of these threads is always the same, and it's been this way going back for years.
1) Noob in DWC asks why his plants are dying.
2) Noob casually mentions he started with plain tap and bumped it up to 100-200ppm in fear of going higher
3) Another noob will suggest he flushes, because that's clearly nute burn!
4) The noob can't tell if he should flush or finally let his plants eat
4) RIP
5) Someone asks noob to take a look at the roots. The roots are dead/dying.. (shocker)
A week later and the plant is still dead. They conclude the plants died because of either
a) water temps not below a certain point
b) didn't use benneficial bacteria
c) didn't sterilize the water
The cycle continues.