First Grow Need Help!

First grow ever only 19 yesrs old. Recently I dont know what has been happening to some of my plants, they have been getting very light green/ yellow. I have enough co2 coming in from outside as I have a fan blowing air in and a scrubber blowing air out. I have 3,600 watts set up under 20 plants with dehumidifier and a/c for ideal temp & humidity. Only thing I can think of was that i veged for 11 weeks @ 18/6 then last week was kept at 24/7 due to some problems that I almost had to get rid of plants. They are about 5 days into flower now, had some heat stress & about 60% humidity & very little watering during that 1 week of 24/7. I know this was all very bad but it was either that or they had to be killed. I have not been able to get them to restore their color and more of them are starting to become more yellow. Please help dont want these babys to die! (Also some of them look weird because they were sprayed with a solution to prevent mildew as the humidity was relatively high during that one week)