Brown spots

[Kojiro]

Cash crop auto
Medium biobizz light
270w meizhi led light
6 weeks from seed
Only fed water so far
16ltr smart pot
Ph 6.5
No misting

Hi all. Back again with another problem. Over night brown spots have appeared on fan leaves from bottom to half way up. I havent fed them yet as they looked great. Wondering if its phosphous, magnisium def or red fungus.

 

[namvet25]

You should started feeding bloom nutes along with cal/mag asap.

 

[Kojiro]

Started feed and cal mag. Hope that sorts it , though after feed last night they look worse.

 

[Kojiro]

It’s magnesium deficiency... mix up a batch of foliar spray... 1gram of Epsom salt in one gallon of warm water, let salt dissolve for a minute or so... add mix to spray bottle, spray liberally top and bottom of leaves over entire plant. This will help immensely with your issue. You can use CalMag... but Epsom is literally the same thing, and MUCH cheaper than the bottled nutes.
Just do not use the “Fragrant” Epsom salts or your plants will smell and taste the same!
Holler if I can help in any way...
Tree✌

Thanks. I already had some cal mag, so ised that.

 

[Kojiro]

Right, have fed both plants twice now with bloom and cal mag. Didnt have a plain water feed inbetween because the plant with problem didnt improove after first feed. Both plants are Barneys cash crop, and as you can see are looking totally different. The problem plant is getting worse not better. Brown spots are on leaves throughout the plant. Any thoughts would be appreciated.

 

[Waira]

... well, with the feeds going in now, that's good,... I need a closer shot of the leaves please, but some of it looks like P defc.; might be hard to get ahead of it now with the high demand and mid-late bloom stage, but most importantly buds are fattening! How close are the lights? P and Ca defc. can have some overlap in appearance, so that's why i asked... lights too close can make Ca defc, go apeshit, even with extra, and it's very possible to over-do the Ca0Mg and kick off other issues... don't sweat it too much, the buds look fine, sugar leaves OK too so crappy fans at the end won't be a detriment to the product!

 

[Kojiro]

Hi Waira. Heres some close ups of leaves. The light is about 20 inches from plants.

 

[Waira]

:smoking: that helps! ...see how it's eating up along the veins? That's a tell for Ca defc.... Stay on the Ca-Mg, that it's just the one tells me in part at least this is a pheno' thing, some plants just are bitchy about Ca! Damage doesn't repair, so look for halting on progression... keep the bloom nutes coming too!