We are very impressed with this new offering from Hozelock as after years of research they have come up with a brand new idea in the world of pond filtration. The key feature comes as part of the filter sponges which are housed inside the main chamber of the unit. They come as moveable sponge blocks rather than the more conventional solid rings or blocks, meaning that when the cleaning handle is turned these blocks give up their debris very easily resulting in a very easy to maintain filter. When combined with the pump supplied you have yourself a sensational piece of kit! Suitable for goldfish ponds up to 8,000 litres and koi ponds up to 4,000 litres. This set contains the following components (please click links below for more information): • Hozelock Aquaforce 4000 pond pump (note: skimmer not included when purchased in this set) • Hozelock Bioforce Revolution 6000 pressure filter * Saving made when compared to buying items separately.