In addition to all the known advantages of the X-Pro Filters, the X-Pro 2000 UV has an integrated UV lamp. The UV-C radiation lowers the level of the harmful bacteria in the aquarium and protects against fish diseases. Of course the unique 24 hours Service guarantee (during the warranty period of 3 years) also applies to the X-Pro 2000 UV. Foam-set for X-Pro filter Foam set consisting of two fine (white)and one coarse (blue)filter foam for X-Pro filters. Available in five different sizes for X-Pro 400, 1000, 1500, 2000 and 2000 UV. Cartridge with Activated Carbon for X-Pro Handy cartridges with Activated Carbon for replacement. Each filter has a different size cartridge. The Activated Carbon absorbs dyes and toxic substances from the water. Replace the cartridge once a month for best results.