Dennerle Filter Extension DE-FX
This fasten-on filter is compatible with the Dennerle Nano Corner Filter and Nano XL Corner Filter. It can increase filter capacity or provide short-term additional filtration when used with phosphate binders or activated carbon. This is particularly essential for aquariums with fish. Simply load it with media and rinse to wash away any residue caused by abrasion in transport, and then put it on your filter. This extension can be used to contain biofilter granules, algae stop, or activated carbon.