looks to me like you had a nitrogen deficiency (even fading to yellow in lower leaves followed by chlorosis) and the beginnings of a potassium deficiency(brown spotting on lower leaves with a piney/olive appearance to leaf color) that was corrected 2 res changes ago and - if anything - your current load may be a little high on nitrogen(deep green, nearly blue appearance in new growth concentrated toward the plant top)
also, nitrogen abundance would be antagonistic to calcium, causing the recent calcium deficiency evidenced by the brown tips of those otherwise very green leaves
get an ec meter and your problems will be solved
meanwhile, i'd back off the nutes by a milliliter or so of whatever has the nitrogen in it and watch my growth
do you know how difficult it is to convince a plant to become deficient in a micronute without some underlying cause? like by sheer usage of that mineral? - ime near impossible