Actually, if you are using GH nutes ("im useing general nutes") and you are in the middle of flowering, I think you are starving them. I believe you need to increase your ppm's. Make sure you are using the micro & bloom and not the grow. The micro will provide a good amont of nitrogen.
About a 2 years ago, I was following suggestions in here about keeping the ppms below 1000 and I always had a lot of premature yellowing in the flowering phase. Then, after reading several companies nute charts, I set up an excel sheet to anlyze the nutes I was using so I would know how many total ppms I would have from a given mix of several dif nutes. I increased my ppms and wah lah. Nice and green and very healthy. Now... in the middle of flowering, I am running at about 1440ppms. I avg about 6 - 8 oz (rock hard crystally bud) per plant with very little larf. However, I do use other nute supplements and I supercrop and de-larf my plants. This maximizes the lumens absorbtion and allows the upper buds to absorb all the nutes (instead of sharing with the larf).
Good luck... let us know how it goes.
BTW... I grow hydro in Rockwool.