Getting brown patches on upper leaves of my plant

[CraycrayQ]

Starting to get brown patches only on top leaves of the plant. Just trying to find out if its a nutrient deficiency or nute burn. Thanks.

[Chefbjy]

Ph? Ec/ppm? Medium? Nutes? Calmag? Need more info.

[CraycrayQ]

Sorry. Soil is FFOF and using general organics flowering nutes. Been using calmag also, but only a light amount (tsp per gallon of water) i dont have a way to test soil ph but the water i put in is always around 6.

[Chefbjy]

You can check soil ph by the run off that comes out. If you don't have an ec/ppm pen it's a good investment. It will help you avoid nute burn and let you know if it's a lock out. Have you checked for pests? With that amount of calmag you shouldn't be getting a deficiency but it could very well be locked out from too high ec.

[9fingerleafs]

to me it looks like classic cal mag hunger, like chefbjy said it better to know all you can about the soil to know exaclty what the problem is, could be a deficiency caused by another problem and the solution its not always just feed more (:

[Campesino]

Just chiming in to concur with Chefbjy and 9fingerleafs .
looks like a little tip burn as well so EC likely too high. Certainly looks like Ca deficiency (brown spots).
Certainly monitor EC, best $15 you can invest in your grow. Without that info I’d prob rec flushing to correct conditions causing current issue.