Rust spots on leaves. Any ideas??

[Watweed_2009]

Hi guys and girls. I'm entering late flrower now some are behind others, but I have these rust spots over a fair amount of my leaves now, any ideas using biobizz nutes in tropic mix (coco Pete) they are still looking good but lower leaves are yellowing a bit I just plucked what I could see. I think it may be nute burn a bit. Let me know what you think please

 

[Kyote]

Hi guys and girls. I'm entering late flrower now some are behind others, but I have these rust spots over a fair amount of my leaves now, any ideas using biobizz nutes in tropic mix (coco Pete) they are still looking good but lower leaves are yellowing a bit I just plucked what I could see. I think it may be nute burn a bit. Let me know what you think please

You may have better luck getting input if you post up in the infirmary

https://www.autoflower.org/forums/autoflower-infirmary-for-sick-plants.90/