strange spots on the leaves

I would say the time arrived last week :P definiteyl start a healthy feeding regimen... if still worried ensure pH is proper with a slurry -- realize it's lower or higher than what it reads relative to what you put in... so, if it reads lower than what you put in, it's likely even lower than that. don't take off top.. need something near root zone, so this ends up damaging some roots... not so good. runoff can do similar and less intrusive, but probably not as precise.. neither is accurate. so, fire her up!

Hi! Are you using a rich soil or a inert medium? Because it seems to be inert like coco fiber. Anyway, it seems to be a deficiency of micronutrients, it could be magnesium, zinc, copper, or sulfur. So the first thing, if you're using an inert medium, is to add some rich matter. If you know exactly what mineral is missing, you could use a liquid nutrient to add it. So my advice is to add a rich matter like compost tea or earthworm humus because they are full of micronutrients and microorganism. If the soil is already rich, it could be a absortion problem due to the pH at the roots is too high or if the plant is overwatered. Minerals tends to get locked at higher pH levels and is better absorbed by the plant in a more acidic root environment. Some deficiencies can show up if the plant is overwatered, even if the pH is right and the minerals are there. So keep an eye on pH and water levels. I hope this has been helpful to you. Good luck!!!

Everyone here might be right! I do believe they are. Foliar spray could help it...

Are you using a soil with added nutrients? or an inert medium? without any added nutrients you need to start feeding them asap as this is them asking for it! Happy growing!

Hi! If the led is pulling 500W from the wall it might be too much for the plant to handle at this stage or there might be imbalance of nutes in the soil. I suggest that you raise the light a little bit and give little bit of nutes (Mostly N,K and micros) Do you have a pH and ec meter? What is your soil/run off pH? Sometimes the deficiencies are caused from wrong pH in the media