blue cheese. Phosphorus problem ?! need help

[Prince_Fajita 32]

okay guys got some blue cheese plants around 4-5 weeks into flower, theyre real heavy feeders. but one plants going a bit weird. random fan leaves started blotching slightly, came back to the tent after a couple daysof my old man tending it and hadnt told me what happened. the ones that hat started blotching had curld up with big brown patches (doesnt smudge not mold). trimmed the dead fan leaves off flushed the plant and it seemed to slow down. buds and sugar leaves are fine just a few fans. been reading up and put it down to phosporus deficiency. no pics atm but its in soil from seeds and im using old timers bloom and a wee bit of calmag. anything with added phosphorus or something you guys could reccommend seen meal worm tea and stuf like that. im going to grab some pk boost this weekend anyway as im out, you think that'll help or something else i could do with ?

any tips appreciated 

PF

[zero 2,996]

its hard to accurately diagnose with pics , but without its double hard .... ime this kinda thing sometimes happens no matter how well they are treated , experience has taught me to do the opposite of 'add things' , so if it were me I would be inclined to cut back on any food , make sure they aint too close to the light , and hope for the best .. the books will diagnose it as a calmag problem ..but it could just as easily be a myriad of other things 

[craigfjyp 5,971]

what's your lights off temps mate?