The Silicabuster DI Filter is perfect for hobbyists that are having algae issues, or those that want to ensure there is no silicates & phosphates in their RODI water. This DI cartridge is 3/4 filled with our Mix-Bed virgin color indicating DI resin and the other 1/4 is filled Anion resin to remove silicate and phosphate from RO water. We only use USA-made resin and cartridges are hand-packed in the USA! Features Extra Color Indicating, Silicate removal, resin! USA-Made Deionization Resin Nuclear Grade, Color Indicating, Virgin DI Resin Refillable Cartridge Hand Packed in the USA! The Silicate Blaster Fitler includes more of the DI resin that removes silicates and phosphates. This filter is great for those with higher silicate or phosphates levels in their water. Or, those having some algae issues in their aquariums. As with all of our Deionization filters, our DI filters use USA-Made DI resin and each filter cartridge is freshly packed in our Winter Park, FL facility.