Having problems :(

Hi all haveing bit of a problem currently got x3 cookie kush and x3 liberty haze.
1.2-1.2-2m tent
600watt hps air cooled hood
8inch outtake
5inch intake
Nutes...Cana a ..Cana..b
Medium coco in 20ltr pots
Adding cal mag
As you can see last couple weeks got this on the leaves now I'm thinking my ph meter is fucked as I've been making my ph 5.8 but but haven't calibrated my pen since last grow few months ago plants are currently little shy of week 7 any help be greatfull think I've stated it all....cheers

Bugs?

No checked for spider mite etc and have had a real good look in coco medium ect always keep my environment spotless too so crossed that out ?

Then i would say calcium deficiency.

Even with adding cal mag throughout?

What are the ppm's/ec you're feeding? It looks nute burned.

Around 600ppm

Are you able to calibrate your meter? Buy a new one?

If your PH is not within a "correct" range, many of the nutrients you provide to the plant will simply be unavailable. Even the additional Cal/Mag you've been providing. PH must be within a good range in order for the plant to be able to absorb those nutrients.

Your pics, IMO, suggest a serious PH issue and/or nutrient deficiencies as a result.

New pen on order as of 10min ago and calibration solution as I've got gut feeling out one is way out or needs another calibration but for what it cost not worth the hassle. Cheers people as I said I think it's a ph problem that now causes other problems like nutrient uptake ect hopefully it's the ph I'll calibrate the new one and then check the same water with new one soon tell me. Been big help many thanks

Get one of those cheap $5 aquarium PH testing kits as a backup in case the pens die or start acting weird.

I found a great spot to download FREE POT BOOKS. I downloaded a grow bible first and got lots more. Books look great and complete like the real ones I have here. No web site but just a page of links. Just right click on what you want and then "Save Link As" to download so they don't open first as some are 50+ megs. They got lots. Enjoy.



Have you had high temps lately? Leaves almost look nute burnt. Read all the little clues on that chart and you should be able to figure it out.

Good luck!