Issues 4 weeks into flower help dwc

Im doing my first hydro grow i notice thst my leafs are wilting any one had this issue. Im growing with advanced nutrients, hydro gaurd.

First thought would be issue with dissolve oxygen. This could be an issue with air stone/pump, or could be something like solution level or temp.

If i get stumped with issue like this would make more detailed post with a few pics and tag peachfuzz.