I use T-5s exclusively from veg to bloom and do okay. But then again, I grow autos b/c they're short and fluorescent lights quickly loose strength the further away the plants are from them. From my experience, "auto-runts" do well under T-5s from start to finish as long as you don't expect as much of a harvest as you might get from more powerful lights. You're invited to peruse a grow journal I completed recently. Just follow the sig line below.I often wonder if folks have any luck blooming under aT5?