Maybe that's what's happening to mine. They're under 2 HLG100 3000k and a Yuson1000 (100w with some red diodes). They're 22" tall at 5 weeks, getting ready to stretch:The red spectrum causes them to stretch, from what I’ve read. It’s honestly the reason I get the big plants….I add a redder spectrum 3000k cob as they’re entering flower and they take off. It causes lotsa tops to reach for the sky. Probably what’s happening in your tent also.