It doesn't look like bleaching/burning from the lights being too close to me.

I've heard of people running into wild calcium fluctuations from using distilled water, but I'm not entirely sure how this may vary with bottled water. While you wait for a more accurate diagnosis, it would be a good idea to at least get a liquid pH test kit and find out the pH of your soil. The kits are inexpensive, and they're easy to find at pet stores, Walmart, and the like. Water your plant with enough pH-neutral water to produce runoff at the bottom of the pot. Collect that excess water, and test the pH of it. That's your soil pH. It's not exact, but it's a good start. Soils high in peat generally lower the pH unless something was added to stabilize it.

Best of luck, and try to be patient while you wait for the renowned CannCom 'green-thumbs' to show up. They'll be here. :jointsmile: