Any clue what I am deficient in? Only found on a f...

Give him Calcium Magnesium

heh, ignore my 2nd sentence of first paragrpah, lol.. as i thought it through, that initial thought turned out partly wrong about pH anyway.

Potassium deficiency symptoms. Not enoug info to rule out pH or nute lockout. These things usually cause more than 1 symptom and can be confusing to diagnose. This seems pretty straight forward to me... If k is being locked out by pH then you'd also have P, Ca, Mg issues which each get locked out sooner. in other words, your plant would be a mess if it was pH if i am right about the k-def symptoms. if in soilless/hydro, K should probably be around 180-200 ppm in your feed, as calculated from guarnateed analysis labels, but this depends on overall ratio of other elements of fertilizer (lockout concerns), normal pH (impacts resulting ratios of nutes for healthy plants), and overall concentration of your fertilizer.... if 1.3-1.5ish EC and anywhere around 6pH, it's probably a good number to compare. If significantly lower, would reinforce the guess about K-deficiency. there are apps and online ppm calculators that can take the infor off labels and spit out ppm at input concentration/dose. If not in usa, consider any differences in labeling rules of your region. Believe UK does something different with p or k, for example. if in soil, this is more difficult to quantify... but again, i'd feel pretty good about bumping K a bit in your fertilization. start slow.. It is always easier to add than take away.

check the ph of your run off and soil we need to know more about it