New problems for the rookie!

Ok I first I had nute problem that I Think I corrected now I have this new problem with all the bud sites on one plant where all the bud sites are yellow and not turning green can someone help me here I added another oxygen stone to get more air in my reservoir thinking it may be early root rot! Any a nd All help welcomed!

What bulb are you using, and how close to your plants?...

Just found this; possible sulphur deficiency?
http://www.ilovegrowingmarijuana.com/micro-nutrients/

400w hps I also did the hand test and I didn't feel any heat what song ever between my hands the bulb but I'll raise it up more

What you got in your soil?

I'm using gh flora series in DWC I just added some Epsom salt to see if it would make a change

In need of some help man I think she is going into shock! icu! I just wanted my baby to get her green back!

I was wondering if it's a good idea to empty my reservoir and use straight water for maybe a week then start using gh flora series all 3 parts all over again!