Sorry, in your other thread I failed to notice you are hydro, that rockwool cube is small, and from what I know maybe cut waterings to 3 or 4 and up the time they get it from 5min to 10min, 6 times a day seems like a lot to me. BTW your plants don't look bad at all; some minor crispiness and yellowing happens in hydro too (can happen) but they don't look like they're suffering.