I bought a double t12 bulb lamp and i could only afford one bulb at the time so i was wondering if the lamp will completely work with 1 bulb. When i connected the single bulb in one socket it seemed very dim and when i connected it to the other socket it glowed orange at the ends. It needs a 20 watt bulb but im sure its supposed to be bright enough. Does it need the other bulb to work properly? plz help