Spotted leaves: need help

[shathaway]

I have one plant that is having some spotting on the leaves BCN Critical XXL Auto, while my other plant, Girl Scout Cookie Auto is just fine. All factors are the same, soil, light, water and age. Its only on leaves hear and there. Water PH is 6.5, I don't have a way of testing soil PH yet. Air temp is 70f. Light is 300W LED about 15-18 inches above. I have 2x2x4 tent with this and only one other plant at the moment(more seeds on the way)

I am using Fox farm trio of nutrients. Currently at 1.5 tp per gallon Grow Big, 1.5 tp per gallon Big Bloom and 2 tp per gallon of Tiger Bloom.

Soil was Miracle grow organic in 3 gal pots.

Not sure what my issue is?

Thank you for any help in advance,

Steve420

 

[StoneOtter]

Hi Shathaway, the pic is one I found that has magnesium deficiency from 420. I can't tell for sure if these symptoms are the same for your plant(you can see better) but if so you need to up the magnesium. when feeding. Make sure ph pen is calibrated too. Good luck, she looks nice otherwise. Nice training. There's a link on the bottom of my sig. for the pest and problem solver. You can read more about it. Also don't worry to much about being close to the light. Unless you know how close to get be careful for light burn. The closeup pic shows a little cupping on that high cola. Might be due to light burn but I'm not sure.

 

[shathaway]

My lighting is 300watt led about 15-18 in above. Is there something I can purchase at a home depot, Walmart or tractor supply(about all I have access too) for the magnesium you would recommend?

 

[StoneOtter]

Here's what the problem solver says.

Solution to fixing a Magnesium deficiency
Any Chemical/Organic nutrients that have Magnesium in them will fix a Magnesium deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!)
Other nutrients that have magnesium in them are: Epsom salts, which is fast absorption. Dolomite lime and or garden lime (same thing just called different) which is slow absorption. Sulfate of Potash, Magnesia which is medium absorption. Worm Castings, which is slow absorption. Crabshell which is slow absorption. Earth Juice Mircoblast, which is fast acting. (a must buy!! Has lots of 2ndary nutrients).
Now if you added to much chemical nutrients and or organics,( which is hard to burn your plants when using organics) You need to Flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

Picture one shows a mid grade magnesium deficiency.

 

[StoneOtter]

My lighting is 300watt led about 15-18 in above. Is there something I can purchase at a home depot, Walmart or tractor supply(about all I have access too) for the magnesium you would recommend?

ABove