Help with brown patches on leaves

Does any of this look familiar to you all?

I mixed up a hot batch of nutes last week, and the next day I saw brown tips so I lowered the PPM and they went away.
I also have a 315 LEC about 20-24 inches above the plants.
PH is 5.8 and pretty much stays there
GH Trio Nutes 330-350ppm
Also my tap water is 80ppm from the tap. I added 2ml of calmag in with a top up yesterday.
Thats 2ml for the whole 20 gallon system.

Here is another pic and a pic of the roots. The roots are much whiter in person, this camera is kinda funky with the contrast under the light