Can be used as the 3rd stage for 20 in. Effectively reduces iron and manganese. Reduces pipe and water heater damage caused by iron, hydrogen sulfide, and manganese. Replacement filters for iSpring whole house filter systems (fits systems WGB32BM and WGB22BM). Powerful Iron & Manganese Reducing: iSpring FM25B is specially designed for iron & manganese removal, reducing iron (MAX 3.0 ppm down to 0.01 ppm) and manganese (MAX 1.0 ppm down to 0.01 ppm). Efficient performance: Higher linear velocities than conventional media delivers high Flow Rates & very low pressure drop. Feed water pressure: 20 – 100 psi. Pressure impact: up to 5 psi drop at a flow rate of 8. Gpm Flow Rate: 4 – 8 gpm. The iSpring FM25B effectively removes harmful substances, improves water quality and protects family health. Excellent Stability and Durability: Stable and satisfactory performance at wider pH range 5.8 – 8.6 and temperature range 40 – 113F. Lasts up to 3 times longer than green sand due to the catalytic media not being consumed in the process. Gpm filter life: 45, 000 gallons at 3. 0 ppm iron level. High Quality Requirements: Safe for Drinking Water Applications. Manufactured to comply strictly with FDA standards and tested by independent third party against NSF/ANSI standards for water quality, material safety and structural integrity. We stand behind our products and if you encounter any problems with any of our products please reach out to us immediately. We are happy to help! Please get your water tested before purchasing this product. If the iron level is above 3 ppm, or there are other contaminants in your water besides iron, we recommend adding a pre-filter, or considering our WCFM500K whole house water filter. How Can We Help? ISpring whole house filters. Number of filters included. Whole House Replacement Filters. Water Filtration System Type. Whole House Filter Replacements.