I am setting up my first planted tank and need some advice on lights. Its a 140 Gallon tank....its 48 inches long 24 inches deep and 28 inches deep.
Was looking into T5's....would quad T 5's be okay for this tank?
Is the tank 24 inches high or 28 inches high? Assuming it is 24 inches high, the front to back depth of 28 inches will require two rows of T5HO bulbs across the top in order to get reasonable uniform lighting. A single T5HO bulb, with a very good reflector, will give you 40-50 micromols of PAR, which is a very good light level to use. You can get Catalina Aquarium to build you an extra wide light, using a housing made for an 8-10 bulb light, but with only two bulbs in it, widely separated. http://www.catalinaaquarium.com/store/product_info.php?cPath=71_194&products_id=1820 for example. That would let you use just two T5HO bulbs and get good lighting too.
If a light is raised high enough above the tank, the light spreads out enough to cover a wide area. So, another option would be a 4 bulb T5HO light, raised about 36-40 inches from the substrate.