leave problems again ... 3rd grow in a row

[Smeg]

hi all
thanks for looking in..
Strain . = Blue cheese
medium = Coco 80%/ hydroton 10%/ Bonemeal and fish blood with bone 10%
Nutes = Canna Range . i follow the chart on website mix in 100l tanks and hand water
i check PH all the time and let normally start of at 5.8 ish
my Temps have been creeping up a little , one day last week they hit 32C /89.F , but that was at the top of the tent ... at plant lvl it was 29/30 c
im currently battling Spider-mites and Fungus gnats ..... not seen a live spider-mite for 2 weeks now .. and the fungus gnats are almost gone too
looking at the leaf-deficiency-chart-..
its looks like nitrogen deficiency ,what do you guys think ?
i was thinking about making a TEA but ive never done this and dont how bonemeal to use , or change nutes to GH range


below are the links from my other grows where a had leave /plant problems
thanks for any advice .comments
smeg

http://www.marijuanapassion.com/forum/showthread.php?t=61637
http://www.marijuanapassion.com/forum/showthread.php?t=60065

 

[Menimeth]

It looks like a Mag Problem to me, I would add some Cal-Mag if I were you.

 

[Smeg]

I have some cal-mag , do I add this to just water ... or do i put it in with my nutes
thanks

 

[Menimeth]

I do both until the problem disappears when It happens to me.

 

[Locked]

Yeah looks like a cal/mag problem to me as well. I hve found most strains seem to need a bit of Cal/Mag added to the feed/water regimen during veg...especially in hydro applications but also with soil. jmo

 

[Hushpuppy]

I would be inclined to suspect magnesium deficiency as coco is notorious for locking up copious amounts of Mag, and since you are in a soilless type of setup with coco as the base medium, that is a likely issue if not thee issue.

Also battling critters can throw the plants into a bit of a tailspin if you are using chemicals for killing the critters. You have to keep a close eye on the PH during that time. However I am still inclined to think calmag. I grow in coco and I give my girls 5ml of calmag per 10L of water every time I add water from beginning to end. In a soilless setup I would start with 10ml per 10liters of water for the first month then cut back to 5ml after that. That would offset the coco magnesium lockup thing that occurs with that medium.