My mother's have just started yellowing the tips and getting these brown spots I've seen a few pics of possibilities but would like more of an opinion.
These are generally feed as and when I see they need to be this yellowing of the tops came on quite quickly after lst and opening up the plant. The plants that haven't got the brown spots are nice green
Nitrosol original and Goliath
0.4 usally. Last feed 0.7 ec
Looks to be calcium or manganese difficiency there with those spots. It could be locking out nutrients or just used all that was in the soil up. Check PH and EC of your soil with a slurry test or by checking runnoff and act based on that is my best suggestion. Hope this helps, those brown spots are unfortunately very familiar to me. Haha
Yeah could be the start of a lockout or a CalMag deficiency, since your feed is fairly light I would be leaning more towards a deficiency, have you got any epsom salts? if so a foliar spray might be the way to go here. One of the soil lads may have a better idea but considering your under LEDs they do tent to increase the need for calmag a bit, well in my experience they have anyway. Being in soil you want that PH to be a little closer to the 6.5-6.8 mark from memory, I run coco so I shoot for around 5.8-6.0. So 6.4 isnt far off and you are feeding lower nutrient levels, It looks more like a calcium deficiency than a mag deficiency though.
Awsome thankyou for your replies ill test the soil and it was as I expected mag or calcium I couldn't decide.......ill mix up some Epsom salts I think As I'm not sure where u get a calcium feed for em any more opinions I'm open to anything cheers
@austin15 you can use gypsum, agricutural lime or bone meal as a top dress to correct calcium deficiency's but in this case I would give them a spray with epsom and see how they fare, then you can go down the route of the top dressing if needs be.
@bubblehok oh ok cool thanks I've done it once before and it seemed to burn the leaves at what dilution would you recommend?
@austin15 I use 1.5 tablespoons to about 5 litres of water, you can go heavier dilution but I find less is more with epsom salts. Can always spray again if it needs more but cant undo a heavy dilution once its on the leaves.
@austin15 All good bro, try do it just before lights out man you don't want the lights to evaporate it too quickly.
Well done what you guys suggested and worked perfectly thanks heaps look mint now
@austin15 Nice, well done everyone 
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