I bugged the piss out of the mods a week or so back trying to understand the benefits / detriments to a 24 hour light cycle. Short thread. Start here:
As I understand it, once you hit your DLI for the plant you’ve maxed the growth for the day in the conditions you have (nutes, temp, water, co2, etc). You can hit it that total by adjusting light intensity in 12, 18, 20, or 24 hours. Doesn’t matter. Any extra light you throw at it will just be wasted electricity for the most part. You won’t hurt it in a 24 hour cycle, but you won’t get the 6 hours extra growth compared to an 18 hour cycle. Note that I’m not an expert, it’s just how I interpreted the feedback.