CNZ CUV-155 Clarifier for Pond and Aquarium 55W. Included 2G11 55W light bulb lasts up to 8,000 hours. Change the 55W light bulb every 6-11 months for optimum cleaning performance. The product is suitable for ponds up to 4,000 gallons and is ideal for cleaning the green water and preventing nasty odors.
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