Help - blackstar 240 - light burn?

Hey guys been having alot of problems with led since i bought two blackstar 240's my first grow went bad and everyone told me to get cal-mag and it dident really help my leaves still burned away,

this grow i am using soil/pertile and its just normal peat soil no added nutes or anything, and i give it 1mlper liter of biobizz grow about a week ago and 4 days ago i gave it plane water so i dont think this is nute burn as its big enough to handle 1ml in a liter of water and it was over a week ago

i have been using a 250 watt mh light to veg this and just 5 days ago i added one of the blackstar 240's to see how the plant would handle it, i have the led 15 inches away from the top of the plants and it still looks like light burn but i really dont know as i am lost with problems with led, i am thinking of either taking out the led and sticking to mh/hps or having the light even higher,

any advise or if anyone knows whats up please share,
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Its not the LED. The discoloration was just more noticable with them. I had a similar problem and determined it to be a PH issue. peat is rather acidic. Try adding dolomite lime to your soil mix next time around. I didn't do this so have been adding a tsp or two to a gallon of water with each feeding.

I keep my blackstar 240's anywhere from 6"-18 away.

BTW regardless of what the plant looks like in pictures. The default answer around here is ALWAYS cal-mag.... fucking amazing that no matter whats wrong with a plant everyone assumes that.

Check your mediums PH.!........peat moss is highly acidic.....first pic shows early ph issues and locking out cal, other plant also lock out====magnesium.....check your ph!!!!

to raise it use hardwood ash, composted leaves,crushed oyster shells, dolomite lime, etc..............good luck

edit....looks like big D beat me to it^^^^ ..............ha

the plants are too young to have any deficiency in my opinion... looking at the other plants in the background on one of the pics it looks like you totally over did it with the nutes. I think it is rare that you will need cal-mag until you are in flowering, I dont use cal-mag with my supersoil... but anyway, dont stress over it, ... I would say take a break from the bottles...

when you have a good airflow in the room, the leaves that are constantly moving will sometimes change colour especially if they are rubbing against other leaves. .. it looks like you got some of that happening as well... but seriously you see in the baby in the pics? you should not have used any nutes on that baby yet!! yet it looks completely toasted!

EDIT I was just rereading now and you say you have not been giving any nutes.. hm, ... well if the blackstar is 15`` from the tops I can almost guarantee you the LED is not the problem... how far is the HPS maybe it`s heat stress how hot is your room!?

Forget about the other two plants in the pics they are in coco and have alot of other problems ive killed them i think,

the first two pics are from the soil plant and the ph cannot be the problem as its 6.5 and i have no problem growing in this soil under hps only problems when i add the led light, if i took out that led now the plant will be fine again, ive tryd it last grow its only after adding led this happens and cant be ph

The mh light is also about 15 inches away and its not heat stress, i have a fan and good airflow and its not blowing the plants with too much air either

ok, .. personally I like the fan to blow directly on the plants. but that`s not the point here hehe. hmm... you say you tried to put the BS240 at the same time last grow and the same thing happened? is it possible that it is at the same time that you also change something in the feeding? I really dont know what to say buddy even though I dont really like blackstar, I am still using mine and it works fine. I can almost guarantee you that light is not your problem... what are you feeding?

OK the two plants in the background are in coco and led is not the problem there, they were my first try in coco and the ec was too high,

the plant in the first two pics with very slight burn but not on the tips of the plant, i have only gave it a light fed of 1ml of biobizz grow, normally you would use between 2-5ml of it but i wanted to start at 1/4 strength. that was over a week ago and when it needed a drink 4 days ago i just gave plane water, the water i use is bottled water that ive grown many plants with in that same soil so i know its not a problem, that slight burn in middle of the leaves only comes 2 days after adding the blackstar, if i took out that blackstar now and just kept in the hps the plant would stop burning and be fine again. but i want this too work, i might try lime if you think it needs that for led

Also the fan is blowing at the canopy of the plants but now shaking them bad or anything just a nice light breeze moving them

I cant really help you anymore, .. dunno what to say, are you re-using your soil or it`s a fresh batch? I dunno I grow in supersoil and all I need is water the whole cycle for super dank ... you are welcome to visit my journal in my signature to see my results, sometimes I wonder why I am the only one growing this way with LEDs its so fkin easy and the best weed too. I have not looked at my PH for more than a year...

Good luck buddy hope you sort it out...

I am not reusing soil i am using fresh soil everytime and its the same brand of soil i bought a good few bags
theres nowhere near me sells the stuff i need to make super soil ill be very lucky to find lime

Hmm well if you give up on the blackstar and sell it lmk. I could always use a third

Alot of people are asking to buy it lol ive said i would tell another person if i do sell but i want to fix this and find out whats going on, should i try and use lime? and if so can i add it to my water rather than repotting? this is the only place i can get stuff like lime is this one ok?? and if theres anything else on that site you think i should get or add please tell me cause i cant get stuff anywhere else,

http://www.diy.com/nav/garden/garden-care-watering/growing/plant_care/-specificproducttype-plant___vegetable_food/B-and-Q-Garden-Lime-3Kg-10777729?skuId=11268315

Yep that should work. Doesn't disolve that well but still raises the ph. Next round just mi it in the soil

Thanks man, how much per liter should i add of it and also how often should i add it? every feed or every 3 or 4 feeding?

I am getting lime today so i thought id give this a bump, i will try 1 teaspoon per 2 liters of water and see how that gos, how often should i do that? every feed??