Early yellownes in the leaves?

my guess is you are not feeding them enough Nutrients and yes i agree with the other comments too it looks like they definetly need more nitrogen ✌️🏻

looks like a nitrogen deficiency.. so calciu mand magnesium won't do much for that. Those symptoms are not related to calcium nor magnesium. these are 2 different molecules with different characteristics and fill different needs in the plant. did i mention they are 2 different things? LOL, sorry... Grab a leaf chart -- google marijuana leaf symptom chart... even if you have to ask questions here, always try to diagnose what you see based on the chart. a good chart should tell you the difference between mobile and immobile as far as where they show u on the plant... one more thing to help eliminate possibilities. mg issues are not visible for 30+ days after they start occurring. it is an oddball in this respect. So, when you have interveinal chlorosis with spots, that's more likely Mg and you should think back 30+ days as far as how much you have given over that time, because it was not enough. trial and error... take notes as you adjust your formula.. the plant will want mostly the same things in same proportions. You may need to drop nitrogen in bloom, but otherwise she wants it all, all the time. cell growth requires similar things even vege vs bloom growth. drastic shifts are not wise as it can cause odd concentration gradients within the plant or at the roots which wil mess up anything dependent upon diffusion and osmosis. ratio and concentration.. when you find a good combo, it works on nearly all planys with zero issues seed to harvest -- soil may require a little more trial and error compared to soilless/hydro, but should be minimal. don't just blindly give "cal-mag" product... though it may be needed... it is dictated by the components of you fertilizer that you use.. if they do not provide enough ca or mg over time (each one is an individual cause and effect), then you need to add more. if you provide enough and add more it's not necessarily a good thing and can actually lead to problems if it is building up in concentration.

I believe you have a nitrogen deficiency on your hands. Nothing major, just the beginning of one. Little increase in feed should do her some good. Also I noticed some light damage and heat stress from your light being too close to your canopy. You want that to be at least 12 inches away. Hope this helps.