@Legibly1200, Thanks for commenting! The tallest center cola was only 8 inches from the light and was sitting at nearly 1400ppfd with the low corners at 900. I could tell it was definitely light stress as only the colas in the center hotspot were showing symptoms. I raised the light back to 18 inches and reduced the overall par to 800-1200 and they seem to be doing better. Keep in mind I'm running CO2 or these numbers would have completely destroyed my plants. Without CO2 I'd recommend staying between 600-800 ppfd. This is also my first time doing 20/4 hours light schedule which is definitely raising my DLI. When you say you have light burn on tips, that can also be from slightly too much nutrients or even the roots hitting a dry spot in the media. Light burn will encompass the whole leaf edge/margins before completely frying the entire leaf. You might just have some tip burn which isn't usually related to light intensity.
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