Cake Anyone?

Taking care and paying attention to the VPD where the leaf temp is 2 degrees or so cooler than room temp. I've noticed a real difference; they look happy and healthy. They are 31 days old from planting and am wonderring if I should turn them; ceilings are 8'. I'm wondering why the petioles and the internodes are reddish colour is this a deficiency? Watching plants for weird looking stuff. Feeding once a week and foliar spraying pro-silicate once a week. Using amounts listed on bottles or a little less. Only spraying within 20 minutes of lights going out. Using a sprayer that allows you to spray upside down and has a very fine mist . Also wondering if I should use a surfactant in the spray bottle and if so would sunflower lecithin work for cannabis? Just started using a light rail with 2 sf4000, I will be adding another light shortly. Fimmed the wedding cake twice. 2 weeks apart.. Only fimmed the others once. I think it's coming along ok, I' do alot of reading to try to make the girls their best. It sure is a learning curve! We're all trying to grow our own medicine. Happy, healthy growing and smoking!