m0useanswered grow question 2 years ago Start A Diary. Lotta missing information.
Looks like you are doing something like a dip irrigation with LECA and have a reservoir somewhere?? just a guess.
Maybe the temps or PH are off, could also be an overgrowth of something in the reservoir causing issues. Lack of dissolved O2?
Some of the damage gives off hints of thrips or mites but not 100%, so I would recheck the leaves again with a magnifying glass, be sure to check the underside in multiple spots. mite eggs are little round dots. cream to yellow colour. Over all I would guess this is a root issue and something in there is not working for the plants.
Good Luck!