Indoor Spots on leaves

[Cerul]

Hey guys,

It's been a while since I posted..or grew anything. Have been in rough spot for over a year now in terms of housing and I've finally found a space where I can grow again.

I have a mystery Indica autoflower that I've been growing. I'm growing in Promix organic moisture mix and I'm ammending it with Flora Nova grow at 1/4th strength along with CalMag and 1/4 tsp of humic acid and silica powder. The plant is under Mars hydro blurple lights and bushy.

It's been a month and half and has starting to flower and I noticed spots on the leaves. Any ideas?
Also, its very bushy so I'm thinking of defoliating the lower leaves BUT since flowering has started I'm not sure if I should just leave it alone. I don't want to stress it unnecessarily.

Any suggestions/ideas?

Thanks!

 

[Cerul]

I forgot to say that I adjusted the pH of the nute solution to 6.2 and the light is 18 inches away from the plant.

 

[MrAutoGrower]

Gotta take a picture under normal light for us to see it better brother

 

[Cerul]

Hi,
I recently bought new lights and got rid of the blurple ones. The spots have now morphed into big yellow splotches only affecting the old growth....at least for now.

 

[Towlie]

https://www.autoflower.org/threads/self-diagnose-your-plants-basic-deficiencies-list.11/

Check this out I've found it very helpful

 

[Towlie]

I'd say it could be a magnesium deficient personally I'd make a foliar spray with Epsom salts PhD to 6.3 spray the bad leafs and also make a feed of water and epsom salts PhD to 6. 3 and feed your soil when foliar feeding just spay the effected leaves but I'd wait for some better advice I'm sure someone with more knowledge can help you out I mess up most of my grows so take what I say as a suggestion