It is going to be very hard to grow any plants in such a tall tank, assuming it really is 36 inches high. If you had a T5HO light it would be good low light, but T8 is nowhere near enough light. One thing you could try is mosses. You could tie some to little flat rocks and lay them on the substrate. You could get a nice branchy piece of wood, like Manzanita wood, and tie moss to the branches to simulate a tree. Those might do OK with the light you have.
Since the light is brighter up near the top of the tank, you could also get some riparium planters, which attach to the tank walls, and put those over half way up the sides with aquatic plants in them. I think that is what I would consider.