I am trying to replace my light for my tank, but because it is an older hood I am having a hard time finding the light I need. What I am looking for is Marineland Natural Daylight F15T8/18". Does anyone know where I can find this light? Can you use a light that isn’t made by this product but that has the same measurements? I have found other lights in this size just not made by Marineland. I don’t want to buy it though if it wont fit.