I used to grow with Mars lights which are very similar blurple LED's and in my opinion you can take them down as low as 5 inches or so away from the plants, keep an eye out for any bleaching and if it happens just move the light up a couple of inches. I have 2 Mars old style 300w, 2 196x3 Reflectors and a Mars II 1600w, none of them are too problematic for burning.
Bending disaster . 2 plants snapped one mild put it back up n tapped it it's fine just a kink ! But the other has snapped n split open holding on by a thread sonive takes it up squeezing it together so it binds with the plant tissues n hopefully repairs it self over time ! I didn't know the stem is hollow inside ? I can see why they snap now gutted that's 4 plants I've snapped now but they will recover just past 1st week of flowering and hopefully the tissue on the other will fix up theta the worst of them all it's actually a break still attached not sure if it will make it to be honest n it's got all the top bud on it too ..
Here's the pics the one on the left no problems plants still pointing up like a super crop bend but the one on the right looks like a gonna ! Open break most of the way around it attached my thread
Sorry to hear about your first row, autos have been getting my attention lately, I'll follow your grow to see if I pick up any more interest in them! Everything is looking really good by the way
Yah no real issues responding well to my viperspectra 900 watt led . a lil bit of nut burn on leaves not major ! So will be flushing with fresh water this feed n then back to feeding again.
Good selection of flowering /bud sites good height no real stretching tbh be nice to see how big the buds get and the yield / strength led light