Hydropure METALTRAP™ MT-25 25K gal Pool & Spa Pre-Filter guarantees no more stains, no more odors! Upgrade your existing systems by just changing to this cartridge to provide a better filter for better water. Our filter gets what other filters leave behind and you'll be able to taste, smell, and see the difference! Working best to remove rust, sulfur, chlorine, pollen, bacteria & viruses down to 1 micron, and much, much more!