Help

what's happening with my plants?

My first guess would be ph issues. How has your ph been holding? how often do you test it?

What does the root zone look like? I this DWC a lot can't be diagnosed with just a pic and nothing else.

PPM Nutes
PH
Water Temps
Age
Lighting
etc..

I mean you are going to get a general answer from such a general question.

clawing is a traditional sign of too much nutes.