We received a DIY lighting system that includes one MH fixture. The lights worked ( MH and flourescent ) but the electrical box containing the ballist and capacitor needed to be replaced. After labeling all the wires I did so. My problem is that the MH bulb does not work now. The flourescents work so I suspected the MH bulb was bad. I tried a bulb from Home depot (same wattage but for an outdoor security light) to see if it would fire off. It worked fine so I ordered an MH bulb using the same part number as the one that came with the hood (the old one had a crack in it). Now the new bulb will not work either. Any suggestions? Am I missing something simple here? The hood and lights are far from new. Am I better starting over with new components? The tank is 75 gal. There is only one MH bulb in the current hood. Thanks for your time.