Aquarium Filter Sponge Open Cell Foam Sheet Bio Sponge Filter Media Pad HMF Fish Tank Sump Divider (11" Lx 10.25" W x 2" H, Black)

The open cell sponge specifically manufactured for aquarium and pond use has a much larger inner surface area for beneficial biological capacity than the cheap close cell sponge in the market.
The reticulated structure also provides better flow rate of water and less chance of clog.
You can use it in any aquarium or pond filter, sump, wet/dry, canister, power filter etc. or your HMF DIY project. It can be trimmed to any size with a utility knife.
The size of pores is measure in pores per inch (PPI). The sponge with higher PPI has more pores in it. More pores means larger biological filtration capacity but with less water flow through rate and needs to be cleaned more often. It is recommended to use combination of sponge with difference PPI to get the best result.
Specification:
Size: 11" x 10.25" x 2"
PPI: 40 Fine
Color: Black
Includes:
1 piece of open cell sponge