Older Leaves Yellow, Newer leaves burnt?

My little ones are in their 6th week but are beginning to show some issues.


Aerogarden
12/12 Light Cycle
Pumps constantly running.
I'm using RO water because I can get it for free.


I tried feeding them nutes about 2 weeks ago but that didn't help much, so now I think I have nute burn.

The yellowing continued so I tried flushing the water thinking it was the pH/nute burn. Did that every 2 days for a week and didn't seem to help much. I then, tried a small portion of Hydrogen Peroxide thinking it was root rot, the roots still look healthy (nice and white), so that couldn't be it.

Now, it's gotten worse. The older leaves are starting to yellow starting from the tips towards the veins and the newer leaves are starting to look burnt. This disorder is starting to make it's way upwards to towards the newer leaves.

I've tried correcting the pH, flushing, adding nutes, fixing root rot and am out of ideas. Anyone want to take a shot at it?

Edit: Newer leaves show some yellow near the stem and older leaves start yellowing at the tips.

If your using an aerogarden you have to use a hydroponic nutrient solution. If you plants are getting water but no food, they won't survive.

looks more like nute defficiency not nute burn

Nute def, mostly N def. start feeding with 1/4 or 1/2 stength and it should get better