Fuzz, here is the deal, your plants will stretch with that little 13w/32w equiv. because it is not enough light, period. You will not be able to keep them short as your plants think they are in the shade, because of the little amount of light that you are giving them. This will cause your plants to try to get tall. They get tall when they receive little light because usually in nature plants that receive little light are shaded by taller plants, so through evolution the plant thinks in low lights if it puts all it's energy into the stem making it longer that soon they will receive full light from out growing the surrounding plants.
This is the reason why everyone stresses about the importance of adequate lighting.