I veg 6 plants for about 6weeks under same bulb lenght but with 65k temp. It gets kinda crowded though around the last week. Can't tell you how well it will yeild in flowering causei have never flowered under t5 but I think you will do fine with autoflower. Someone correct me if I am wrong. Oh keep well ventilation if you are growing 6 under. I had small podwer mold cause everything was to tight and the air wasn't mving enough. But I caught it soo fast cause it was one small patch cured with serenade. Just make sure if leaves are semi-overlapping that you get fans to get em fluttering off one each other