The Oase BioMaster Pre-Filter Foam 10 PPI is an ultra-coarse replacement sponge set designed to trap large debris before it reaches your canister’s main biological media, maintaining optimal water flow.

These sponges are commonly recommended by aquarium hobbyists as a flow-rate upgrade over the standard finer sponges (30 PPI or 45 PPI) that previously shipped with older BioMaster models, helping prevent rapid clogging and air buildup.