Bag seed, temps are fine, watered with 6.7ish pH water temps never drop below 75 degrees, watered every 2 days with regular water and every 4 days with tiger bloom
Looks like nute burn to me. How old is the plant? Are you measuring your run-off water or just the water going in?
You could just have a picky plant. I would ramp down the strength of your nutes a bit. Nothing can fix the damage, but it shouldn't spread.
Yeah I knew it was damaged for good, I've been plucking those leaves off, there's not many, but I hate making my plants waste energy on shitty leaves