Just hang them from the top. If you go with clones you could probably put about 30 to 40 clones in there, but if using seed I would probably go with about 25 because you will need to grow them out longer than clones in most cases and they will strech more than clones so you may have to do some LSTing and that will take up some space. With those demintions I would try to fit a 8 bulb and a 6 bulb if I remember the measurements of the lamps., but T5's cost a nice little penny. A cheeper way is to use T8 lamp fixtures with T6 bulbs those fixtures are only like $50 a peace compared to the $200 and up T5's. You will not get as many lumens, but you just shuv as many as you can in there, plus you can get those fixtures all over the place with out having to order.
A fellow had a cab on Over Grow with simular measurements and he was pulling almost a LB from it using T8 bulbs, but he was very experienced and had been using strains that he was really familiar with. Well good luck.
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