Hey! I can help 100% as my friend had the same exact issue. They gave him a replacement bulb. Your chain store Petco,PetSmart etc will just send that bulb back to company. It's absolutely worth the trip to the store and get a brand new bulb free.
"When creating an aqua scape, strive for the beauty of imperfection, as its art and there is no wrong or right, it's left open for interpretation" James Findley