Burn spots

[AmericanJesus]

-Problem: Starting noticing burnt-like spots, leaves fading in colours, problem getting worse.
-Medium/grow method: Only coco.
-Feed and supplements used: Hand-watering, Canna Coco a+b 2ml per litre. Feed, rest 1 day, water, rest, feed, loop.
-Water source: 6.2ph water from tab. After mixing nutes, I wait about 4-5 hours after mixing before feeding plants.
-Strain and age: 8 weeks old, royal gorilla from RQS.
-Climate: Night and day 22-24 degrees celcius, 30% humidity. in tent.
- Light used: Mars Hydro TS 1000, 12in away from top of the plant
-Additional info: 7-8 days now.

Initially I believed they were getting too much light, so I raised it 12in (cannot go any higher), too much nutes, lowered from 3ml per litre to 2ml per litre of A+B, ventilation, I added a extra fan, the burnt-like spots are getting worse.

Any help will be appreciated it, TIA.

 

[MMMi]

Twisted leaves always make me think PH. 6.2 is at the very top of the range for coco, probably not ideal. Light burn would affect the whole top of the plant more often than not.

 

[Arthur]

Coco is not a feed water medium... it is not a feed and rest medium. It is a feed every 24 hrs medium, and more likely every 12 hrs when in flower.

Coco needs to be run with a pH of 5.8 to 6.2 if it drys it will mess with the pH #s.

Looks underfed, with a fair calcium deficiency.

Ph of feed needed, and ppm
Ph of runoff and ppm there as well. Betting your pH is off, and ppm very low.

 

[Waira]

... lights are too close, RH% a bit low,... makes for a bad combo! Symptoms look like P defc, but maybe micronutes too,.... the light blasting can cause such symptoms, or trigger boderline defc.'s to start showing because of the stress,....

 

[Kurt6652]

You need to buffer your coco media with cal mag if it was the dehydrated stuff. Unbuffered coco can rob plants of calcium. I am not an expert just trying to help.

 

[AmericanJesus]

Coco is not a feed water medium... it is not a feed and rest medium. It is a feed every 24 hrs medium, and more likely every 12 hrs when in flower.

Coco needs to be run with a pH of 5.8 to 6.2 if it drys it will mess with the pH #s.

Looks underfed, with a fair calcium deficiency.

Ph of feed needed, and ppm
Ph of runoff and ppm there as well. Betting your pH is off, and ppm very low.

I believe this was the problem, I was told to give only water after a feed to rinse the nutrients because they clog up and the plant gets damaged, I've been under feeding for about 8 days now that's when the problems started now that I think about it. I stopped feeding every day because it was developing some sort of fungus on the top which turned out to be the coco was too moist, after feeding less and less, the fungus disappear but left me this present.

... lights are too close, RH% a bit low,... makes for a bad combo! Symptoms look like P defc, but maybe micronutes too,.... the light blasting can cause such symptoms, or trigger boderline defc.'s to start showing because of the stress,....

I can't push the lights any higher but I guess I can tune them down, would going from a 24/24 to a 20/24 help?

You need to buffer your coco media with cal mag if it was the dehydrated stuff. Unbuffered coco can rob plants of calcium. I am not an expert just trying to help.

The coco was already buffered when I bought it, no need to re-buffer I was told.


TIA

 

[Arthur]

If your coco was getting a fungus, there is something wrong with the coco. Due to where coco comes from, it is usually washed (rinsed) in salt water. Unless I've personally checked the pH and ppm of a bag of coco it doesn't get run. If not flushed clean, the salts bind... calcium and magnesium.
Many people I know that run coco feed every 6 hrs.
Yes, the salts build up, and we flush out, but it's not even a weekly thing... this is where the ppm meter comes in. As the salts build up, ppm climb. Out of range, flush and reset to correct values.

 

[AmericanJesus]

If your coco was getting a fungus, there is something wrong with the coco. Due to where coco comes from, it is usually washed (rinsed) in salt water. Unless I've personally checked the pH and ppm of a bag of coco it doesn't get run. If not flushed clean, the salts bind... calcium and magnesium.
Many people I know that run coco feed every 6 hrs.
Yes, the salts build up, and we flush out, but it's not even a weekly thing... this is where the ppm meter comes in. As the salts build up, ppm climb. Out of range, flush and reset to correct values.

I bought Canna Coco, it's quite high rated so I think it was something I was doing, too much water or not enough holes on the pot I'm not sure, but it's gone, it was this weird white-hair spots on the coco, all over the top of the pot, mold/fungus kinda substance, I just lowered the amount of liquid in it and it was gone, I read in other places sprinkling cinnamon on the top of the coco would fix it but who knows what it was or where it was coming from :/ (Newb here)

I've started now feeding twice a day since yesterday, the colour has come back to the leaves! They're not so yellow anymore, and getting a darker shade, I've lowered the ph to 5.9-6 and move them away from the light, seems they're doing better now.

Thank you all for your help, much appreciated it.