purple stem

thinking 2 of my girls are sick, temperature at 78-80f {26-27c} lights on, 68-70f {20-21c} lights off with a 45-50% humidity. Last time they was watered was 3 days ago, last feeding was on the 4th Formula 2: Bud/Bloom 2-4 weeks depending on light and water consumption the soil is still moist not...

So this is the first REAL scary issue I've encountered yet with my gal. After feeding her some banana tea the other day, I noticed her buds getting bigger & fuller but her leaves also started getting more & more yellow & crispy starting at the bottom. It looks like a typical nitrogen...