After noticing calmag deficiency in some other lad...

If the yellowing is only affecting only lower, older leaves it could be that you need a little more CalMag (not sure what you are currently giving them). 2.5 mls/gallon is an average maintenance dose while some plants require 3-5 mls/gallon to remain healthy and green all the way through till flush. If the yellowing is affecting the entire plant all at once- I would lean more towards a Nitrogen/all nutrient deficiency. From what I can see above, you seem to be giving your plants the correct dose of nutrients so if the problem persists I would recommend a flush with PH’d water followed by a watering with light nutes. This usually works for me and I continue on through the rest of my grow to a successful harvest. Hope this helps and all the best growing forward!