Set of 6 filter sponges for aquariums, ponds, and replacement sponges for filter pumps. - AquaForge

Dimensions: Cylinder approximately 6 cm x 3.5 cm, with an inner diameter of 1.5 cm. Please note that these are pre-filter sponges, so they have only one opening. The pre-filter sponge extends the life of your filter media and is reusable after cleaning. Made of soft, low-density black sponge. Installation takes only seconds and lasts from several months to a year, depending on your filter load. The package contains: 6 rolls of filter foam. Effectively removes dirt, algae, and debris from all pool surfaces. Prevents small fish, fry, and other fragile animals from being drawn into the filter. Improves biological filtration.