With this set of practical filter pumps you can conjure up decorative fountains on your garden pond while at the same time enriching the water with oxygen. In addition, the organic active foam filter cleans the pond water mechanically & biologically. A dirt-retention device binds the soluble dirt when the pump is removed from the pond. The "quick & easy clean system" allows the filter to be cleaned just by turning it by h&. Part nos. 573014 & 573015 are fitted with a UVC to effectively combat floating algae.