Hey James.
Follow the advice given in the previous comments. It helped stop the problems I had.
Are you PHing your water? Mistake I made.
Is your water source high ppm? Problem i had.
are temperatures high? Also problem I had.
I think all these things together caused my plants issues but yet they still went on to produce soooo much buds!!! I got at least 8 ounces out of those 3 plants! I was over the moon with the results and I'm smoking her right now still

I worried alot over so many things that was going wrong with them but there such strong plants they just grow!!!