The RFFE20-BB cartridge is designed to provide an easy and effective method of reducing iron from water, which greatly improves the taste.This cartridge helps to eliminate the orange and brown stains often found in sinks, toilets, tubs and other plumbing fixtures.RFFE20-BB reduces the possibility of damage to pipes and water heaters and reduces up to 3 ppm dissolved iron.It adds no harmful chemicals to the water, making it completely safe for drinking water applications.The RFFE20-BB cartridge should be installed on the main cold water line after the pressure tank or water meter. For best results, pre-sediment and post-carbon treatment is recommended. Iron Level Filter Life 250 GPD (4 ppl) 125 GPD (2 ppl) 75 GPD (1 person) 3 ppm26,000 Gal.104 Days208 Days416 Days2 ppm40,000 Gal.160 Days320 Days640 ays1 ppm80,000 Gal.320 Days640 Days1280 Days0.5 ppm160,000 Gal.640 Days1280 DaysN/ARecommended Operating ConditionspH>7.0Silica