Yup, you're behind the demand for PK, likely micronutes too... Symptoms are really advanced now, so not much to do to correct this, just feed well and get them across the finish line... I'd consider getting a synthetic PK booster, because they will be right-now available, the tea is slower to work and not rich enough,... A few hits of this will help get PK levels up, and you can resume the PK Tea... it won't queer the grow, taste or anything like that, organic or otherwise,.... get more kelp going too, that has micronutes in it...
A check of in-pot pH would be wise as well, just to make sure,... but you'll need a pH soil probe for that... The Accurate 8 (Control Wizard) is a good unit for the $, or the identical unit under a different brand name,....