The Green Killing Machine 3W Internal UV Sterilizer Bulb should be replaced every 6 to 9 months (assuming it is used constantly). This Green Killing Machine 9W Internal UV Sterilizer Replacement Bulb is very easy to replace as you just replace the entire housing for the UV. No need to mess around with caps, gaskets and quartz sleeves when replacing your bulb. For the Green Killing Machine 3W Internal UV Sterilizer with Power Head.
