For optimum performance, where (in my tank) should a
Poly-Filter be placed?
Place the Poly-Filter® resale size: 4" x 8" into any filter system after prefilter material. The Poly-Filter may be cut to fit any size filter compartment. Larger filter systems i.e. wet-dry or canisters may have a chemical medium section to which Poly-Filters may be stacked in series which improves absorbent/adsorbant performance. Instead of adding Poly-Filter Discs to cylinder that has too large a diameter - try cutting Poly-Filter 12" x 12" sheets into discs then add the extra Poly-Filter cutoff pieces.