need help diagnosing deficiency asap

i could really use some help with diagnosing a deficiency. about three weeks ago i started to notice little brown patches in the middle of what looked like perfectly healthy leaves and every day it gets steadily worse untill the whole leafs are brown and crispy, i am now worried as they are all starting to show signs if the problem and the 4 plans that was first to show symptoms are looking really rough!

here is what im feeding and info about my crop

strain: blueberry

age: 5 weeks into flower

substrate: coir

ph:5.8

feeding:
canna a&b 38ml per 10ltr
canna boost 30ml per 10ltr
pk13/14 15ml per 10lter

im using a 100ltr reservoir

temp: 78 day 68 night

i flushed it for three days when i first seen the problem, i then thought it might be a phospours problem and hoped theat when i started with the pk that it would help but it didnt and now im stuck!

any advice greatly apprecated

Over!!! I use canna aqua and 3.8ml/L plus the boost is a lot. Plus full strength PK - oh boy! I start with 0.5ml/L. Any idea of the EC/ppm? I'd flush ASAP!!

thanks for your help pal how long should i flush for as there is only 2 and a half weeks left in flower and ive just found thrips in my runn off! would that contribute to the symptoms

Mr Samsung said:

thanks for your help pal how long should i flush for as there is only 2 and a half weeks left in flower and ive just found thrips in my runn off! would that contribute to the symptoms

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Its most likely springtails in your runoff. Especially if they jump around a little.

Most are detrivorous feeders.

If you're using coco then realistically you should EC testing your mix.

By catching runoff and testing the EC vs your mix EC you can get a good judge of how much to be feeding.


To me it looks like you could be over doing it massively.

Pk1314 only needs to be used for at most 2 weeks.





J

Def flush and and use a low ppm of maybe 300ppms of a flowering nute and a little cal/mag. Good Luck

Cpappa27 said:

Def flush and and use a low ppm of maybe 300ppms of a flowering nute and a little cal/mag. Good Luck

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Yes, just do this. You're too late in flower now to fix it.

sorry i havent been on here in a couple of days, i decided to take your advice and have flushed them for the last three days. ill let them dry out as they are soaking at the moment and start feeding at half strength after that!

thanks for all you help guys as i think you may have just saved my bacon, i really appreciator you guys taking the time to help me out