Spots on plants leaves, please help: first grow

[Daniack]

40% Sativa, 60% Indica
2 months old
5 gallon pot
600w HID light (about 22 inches[56 cm] from plant top)
Food:
Sensi grow - from advanced nutrients
BIOTONEX DENSO - from CANNABOOM
Growing in soil, feeding about 0,5 gallons (2 liters) of water every 2-3 days

(this ocures only on few leaves)
I think it could be nitrogen toxicity, as I had that problem once before, but I've been feeding her half the nutriens she is supposed to get for a month now, so I am bit curious what is happening to her.
Overall plant looks good. Bottom leaves are yellowing but I suppose that's normal, because it's proppably caused by not haveing enough light.
Some leaves have claws, but I can't lower the amount of nutriens my plant is getting because I have no other way to balance PH, than my PH perfect nutriens.

Please help me.

 

[HugePeckerhead]

she could be pulling the nutrients stored in the leaves since you're not feeding at full strength. Not saying this is what it is. Please allow other members to chime in..

 

[Emilya Green]

I think they look quite good at that level of nutrients and that you are doing a good job. The spots look to be the start of a magnesium deficiency. Add a little calmag to your nute program, and that should stop this from progressing. You will probably need to give a maintenance dosage of calmag all through the grow on at least the plants that are showing these signs... but it wont hurt to give this small preventative dose to the others too. This problem is very common when under LED light or using RO water since a good part of the extra magnesium we get in our grows can come from tap water.

 

[Daniack]

I think they look quite good at that level of nutrients and that you are doing a good job. The spots look to be the start of a magnesium deficiency. Add a little calmag to your nute program, and that should stop this from progressing. You will probably need to give a maintenance dosage of calmag all through the grow on at least the plants that are showing these signs... but it wont hurt to give this small preventative dose to the others too. This problem is very common when under LED light or using RO water since a good part of the extra magnesium we get in our grows can come from tap water.

Thanks a lot, i'll take your advice and get her some calmag. Hopefully this will solve it.

 

[Daniack]

she could be pulling the nutrients stored in the leaves since you're not feeding at full strength. Not saying this is what it is. Please allow other members to chime in..

That might be it, I will start slowly adding nutrients back to full amount. I am just scared because signs of nitrogen toxicity are not gone yet.

 

[HugePeckerhead]

That might be it, I will start slowly adding nutrients back to full amount. I am just scared because signs of nitrogen toxicity are not gone yet.

follow whatever @Emilya said. she's one of the best go to people here. Her is advice is untouchable and she's very nice. She's one to follow and read up on it you need any kind of information.