Need Hydro expert Plants slowly dying

I went away for a couple of days and came back to a yellow plant. Things have just been getting worst from there. Brown spots started to show up and the leaves are starting to get deformed. I think a low ph caused nutrient lock. I just want to know if there is any thing I can do or are my babies already to far gone. They have been stuck at 6 inches for about 2 weeks know.


I have no idea what to do. I bought calmag and added that still didnt help