Please help my white widows! pics!

Two of my white widows are not doing well. They are under a 430W HPS and have been flowering for over a month now. The leaves, especially the ones on top, have been shriveling, drooping alot, turning yellow and brittle. It also looks like the buds are not developing as fast as they should. Should I flush or continue giving nutes? I am using General hydroponics. I flush them 1 every 5 times I water them. Any advice is appreciated!!!!!

pics are attached.

how often do you feed nutes and water, whay for nutes and what is ph of soil and nute mix? what are the temps

Looks kind of like over-watering to me.