If your looking at this filtration system then your onto an absolute winner. The PF Filtration system is the most versatile, comprehensive and easy-to-use filter range you can buy. The powerful venturi thoroughly aerate the water, and are easily controlled with a simple-to-use rocker switch. Your water will stay clean and clear as the clever patented aqua value lets waste particles enter the filter and then hangs onto them so they don't re-pollute the water. Even better, you can turn off the filter and remove the filter body for cleaning without the fear of seeing removed waste drop back into the aquarium. Its simple to fit thanks to the easily located cradle, and easily adjusted with a simple flow rate and direction adjustment feature. Replacement pads are readily available in separate packs of carbon, plain or super fine.