Has anyone replaced a tube for the 15W BL from Bioquip? Mine is broken and the ends of the light with the contacts and red caps are literally welded to the wires connecting both ends of the light. I always though I could simply pull the red caps off both ends of the old light and then plug the red caps on the new replacement and then put the blue sleeve back over the whole setup again. But I can't get the old bulb ends to separate from the rest of the ballast/plug setup. I assume these are sold to be reused with new bulbs, right?