Change of light caused sickness?

Hi everyone

Recently i moved from a 250wMH to a 400w HPS in order to get things going. Plants started to grow very qick but since changing the lights over im getting these problems with the leaves. I checked out the stickies and looks like it may be a calcium def, but the brown spots are between the veins, so maybe mag? Some leaves are also dying off. Im growing organic and havnt fetilised up to this point, as there were nutes in soil already ( i make my own soil) Like i say they were really doing fine under 250wmh but since changing them they have all kinds of problems.

Heres some photos:

Sounds like they need some food.
Did you check; https://www.rollitup.org/marijuana-plant-problems/488004-guide-nutrient-deficiency-toxicity.html yet?
The pictures in the guide are pretty useful in diagnostically approaching your problems.

Yeah i checked that already, i think you may be right with the feeding im brewing a tea as we speak will see if this helps them any and post back. Also im pretty sure that when you use a stronger light nutritional needs go up fast. So lack of feeding could rightly be the cause. Thanks

Sort of my thoughts as well, you commented that it had a large burst of new growth, and that it was getting everything from the soil before. It may just be time for a nice feeding for her. However, i'm pretty new when it comes to a lot of plant problems. So you may want to wait for further confirmation before just taking it from me.
However, if you feel comfortable proceeding with a feeding, then go for it. Be sure to post results so we can know what the issue really was.

How Close is your Light? what about Temps at Plants Tops Level, Only ask cuz looks like they curling up a bit...maybe I missed it but How Old are they? and How Tall?

Peace

Never seen changing from mh to hps do anything like that, It looks like magnesium deficiency to me. add some cal-mag next time you water.

look here : http://www.growweedeasy.com/sites/growweedeasy.com/files/cannabis-magnesium-deficiency.jpg

good luck

fssalaska said:

Never seen changing from mh to hps do anything like that, It looks like magnesium deficiency to me. add some cal-mag next time you water.

look here : http://www.growweedeasy.com/sites/growweedeasy.com/files/cannabis-magnesium-deficiency.jpg

good luck

Click to expand...

Yeah i saw something like this in coco before but not soil. Will look for cal mag amendments and give some in next watering with feed.

Its not a temp issue ice god air cooled hood and temps are rarely a problem. On previous gros ive had the hood less than 3-4" from tops with no issues whatsoever.

Thanks for all your comments