AA Aquarium Green Killing Machine Replacement UV Sterilizer Lamp; Available in 2 sizes Aquafit Aquatics Online Price $35.98Regular Price $39.97 9 watt - $35.98 24 watt - $64.98 Quantity This variant is currently sold out AA Aquarium Green Machine Internal UV Sterilizer replacement lamps should be replaced every 3-6 months when your LED indicator signals you for the lamp to be changed. The replacement UV Lamp is available in 9 watt and 24 watt.