Oh, my thoughts .. I see now .. I bloomed at around that height, 12-18" .. Some strains shot up to 4' while some finished at around 30" .. You have plenty of ceiling height, but if you veg too tall you don't really gain .. I found finishing up with plants between 2 and 3 feet tall allowed for decent light penetration to help develop the lowest bud sites on the plants .. 5 foot plants usually suffered from poor bud development on the lowest branches because light penetration and light intensity hitting that part of the plant was very weak.