I've always had so much trouble with seedlings under any led, I like to leave them under the t5 for a couple of weeks just to get a little established than under the led, though to be perfectly honest I've also seen where it's been strain dependent as well. My Santa under the led or so I thought it was the LEDs fault was VERY squat with tight node spacing while another strain under the same Cali work 400 in veg mode did beautiful. So nammy if you allready have a t5 and a gn I say it's time to do a side by side and see what works best in your set up. :karma Cloud: of beautiful seedlings!