Need help with my dwc Autoflowers

Hey all, first time growing in dwc and I’ve encountered a bit of a problem and I’m stumped. I’m growing two watermelon zkittles autos in my first dwc grow I’ve grown in soil for years but never encountered anything like this, for the first two weeks my girls were doing amazing they seemed happy and healthy my reservoir had a low ppm of around 120 for those two weeks and on day 15 I changed my res and upped my nutes to a ppm of around 350 and had some minor stretching so I lowered my light from 24 inches to 20 when I did so it raised my water temp to around 75 which in turn seemed to cause signs of root rot after treating it by washing my roots changing the res again and adding hydroguard my plants have taken a turn for the worst I they seem to have slowed tremendously on growth, new growth is very dark green, lower leaves seemed to dry up on the tips and become brittle and the whole plant is droopy and curling under I have lowered the light intensity, lowered my ppm, lowered the water level, added another air stone for more dissolved oxygen my tent stays anywhere from 68-75 degrees, my RH is anywhere from 40-50% my water temp stays between 68-70, my PH is a constant 6.0 and my current ppm is 250 but my roots have turned completely brown but have new white roots starting to come through the rockwool and out of some of the old roots I am new to dwc so any help is greatly appreciated but at this point I’m completely stumped the first few pics are before I made the res change and the later ones are how my plants currently look
 

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Failmore

Well-Known Member
If you can't keep the res around 66f you are going to need to run sterile imo.

So you need a chiller or a sterilizing agent. Hydroguard does not work as intended in a hot tank.
 
If you can't keep the res around 66f you are going to need to run sterile imo.

So you need a chiller or a sterilizing agent. Hydroguard does not work as intended in a hot tank.
I’m also glad you told me that about Hydroguard all I’ve ever heard is people praising the stuff like it could cure cancer
 

shiva71

Well-Known Member
Freeze some water in 0.5l coke bottles and chuck em in. Your roots will appreciate it!
 
they started making that again?? good news. i used that mnay years ago.

get your RH% up to 70 ish if you can.
Yeah I ordered it directly off their website and getting my RH up shouldn’t be a problem I’ve been actively trying to keep it down because I though 70% was too high
 

Failmore

Well-Known Member
Lots of discussions and info about sterile and Bennies on the forum. Do a little looking around and check out some of the dozens and dozens of threads on the subject.
 
Droopy all the time those pics were taken two days ago and they’re worse now they’re still growing but they look just as bad idk if it helps but I’m using a Mars hydro ts1000 at 24 inches on 75% power in a 2x2 tent
 
It seems to be staying wet from my air stones bubbling and splashing water up on the bottom of my net pots the water is about 1.5 inches from the bottom of the pots
 
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