Looking for advice

Hello, we are having a few issues with our grow that I'd like to get sorted ASAP.
4 plants under a 400w led. Temps are now 76 and RH is 26. Have only been fed medi-one at half strength and cal-mag at half as well maybe 3 times. Last feeding was about a week ago and a flush has been done since.

Here's the pics


Plans to give them a heavier dose of both medi-one and cal-mag tonight. Any feedback would be appreciated.

give it full dose of calmag with the normal dose of food

Source water ppm and ph? Brand name of your soil and any ammendments given? Do you know the ppm and ph on your run-off?

Using nutrimix hp. Using ro water. Unsure of ppm but the runoff had a ph of 6.1