I need help

So here it is. These girls are 24 days into flowering. They are in a 4x8 grow tent with 2 sf4000 spider farmer led’s 20-24” above canopy. I am using organic soil using recharge 1 time a week. My water is PH to 6.1-6.3 and my temps when running is 74 degrees. At night it gets down to about 64-66 degrees. I am using CO2 at 700 ppm. I water every 2-3 days. The pictures below are 2 different plants. Showing I believe 2 different problems. I really need some help figuring this out.

Magnesium issues.

First pic looks nitrogen deficient. Second and third look like the already nute burned tips got light burned.
Any chance you're not putting enough fluids through them? Don't want to piss you off if you're a pro but LOTS of people don't put enough fluids through their plants. Hard with bigger plants in soil to drain them. The callout is to wet the soil mass completely and then put 10-20% of the pot's volume in fluids through them; every time. If you haven't been doing that then it gets toxic in the soil. Best to flush hard at that point, but that's only if you haven't been watering like that. From the pics it could explain the lime green look in the first pic and the burnt tips in the rest.