PRE-FILTER FOAM CENTRE & OFF-CENTRE HOLE SPONGE BLOCK POND PUMP CUBE FISH MEDIA
POND FILTER FOAM CUBES. 6” Centre Hole. 8” Centre Hole. 6" cubes have a large surface area making them ideal for straining water entering a pump. 8" cubes have a large surface area making them ideal for straining water entering a pump.