New Grower- need help diagnosing issue

[Craveman]

Hey guys-

On my second grow and having an issue with one of my auto strains: RQS- gorilla auto. She started with a couple brown spots on just a couple of the leafs but has now started to take over (see pics attached). Could really use some expertise on diagnosing as I have been spinning trying to correct. Even if I can’t correct figured it would be good learning what went wrong for my next grow. Below is the Is high level info on my grow with pictures showing the issue. Any assistance is greatly appreciated.

- 2.5X2.5 tent
- 2 150w lights
- grow buckets with aerator
- coco loco with natures living soil concentration mixed per the mfg.
- PH all my water to 6-7
- Fed molasses about once a week
- Started feeding bread bud- Cold War organics about once a week around flower
- some stems are purple

*I have two other autos: RQS Titans in the tent that are really healthy but then the RQS gorilla glue i can’t say the same. I have tried to increase feeding also tried to add cal mag, raised the light and dimmed. Not looking like things are getting any better, if anything getting worse.

 

[Drownomatic]

Not sure what you're objecting to.

 

[Craveman]

Not sure what you're objecting to.

75% of my plant has leaves that have brown spots and turning brown/yellowish. Forsure not normal fade situation. Started just after flowering. Realizing not as noticeable from my pictures but if you zoom in, should start to see it.

 

[Drownomatic]

You're in late bloom, a few weeks left.

I've had plants so the same thing, and they finish just fine.

 

[Driver77]

Looks like a few things went wrong....calcium at some point, maybe some light burn and probably a ph lockout. Guessing I would say probably excess nutes in the soil causing low ph lockout.
Nothing you can do that won't make it worse at this point....should still get across the finish line.
I'm not familiar with grow buckets but usually running an inert media.......coco, perlite, or hydroton work best....organics and standing water cause problems.

 

[stvkc69]

How much light are you giving them? That has been my biggest issue so far. Running the lights to hard will cause nutrient burn and deficiencies all on the same plant. Not to mention stunted growth and loss of yield.

 

[Cannaficionado]

Its too late to change anything and once something goes brown its never gonna get better. For one if you mix in more than 40-50% coco, your medium NEEDS to be treated like its straight coco. Coco does not buffer nutrients so in most cases you will need to feed daily or every other day. Microbes in the soil can help with this but in coco especially if you're watering to runoff you will need to feed more often than once per week. You will see lots of grows end up like this on here, it happens a lot. While its nice to have a perfectly healthy plant from start to finish, in a lot of cases especially late in the cycle stuff like this will start popping up. Another thing to mention is living soil is alive, feeding molasses feeds the microbes but if you dont have organic matter to break down theres no food for the plant. With that said any abundance of veg nutrients carry over into flower as they have yet to be broken down. So this could create an imbalance if you over charged on organic veg feed.

The other thing is 7 is too high of a ph for soil, and well to high for coco. You should be shooting for a range of 5.8-6.3. In 100% soil or a peat based medium the ideal ph is between 6.2 and 6.5. At a ph of 7 some nutrients will never get absorbed and will continue to build up in your soil and cause what is called perception in the medium where they combine with other nutrients and return to an unavailable form that the plant cant absorb. Once one nutrient builds up enough it will begin to antagonize the uptake of other nutrients creating a snowball effect. A lot of what you're seeing on the top of the plant is a calcium and magnesium lock out. Not sure if this is from ph or nutrient imbalance. One thing to note is that even if you're growing 5 of the same plants you could still have one that leans on other genes in its pool and will have to be treated slightly different than others. This plant here could have been a light feeder where as the others were unbothered by the amount or ph of the solutions you were giving them.