iSpring FM25B
iSpring FM25B Whole House Iron & Manganese Reducing Water Filter Cartridge User Manual
Model: FM25B
Introduction
This manual provides instructions for the iSpring FM25B Whole House Iron & Manganese Reducing Water Filter Cartridge. The FM25B is designed to reduce iron and manganese in your water supply, improving water quality and protecting your plumbing and appliances. It is compatible with iSpring whole house water filter systems, specifically models WGB32BM and WGB22BM.

Image: The iSpring FM25B filter cartridge, highlighting its effectiveness in reducing iron (up to 3.0 ppm) and manganese (up to 1.0 ppm) to 0.01 ppm.
Setup and Installation
The FM25B filter cartridge is intended for use within iSpring whole house water filter systems like the WGB32BM and WGB22BM. For optimal performance and to extend the lifespan of this filter, it is recommended to install the FM25B after a sediment filter and/or a water softener.

Image: Illustration of iSpring WGB32BM and WGB22BM whole house filter systems, indicating where the FM25B filter is typically placed.

Image: A diagram illustrating the recommended installation order: sediment filter, water softener, then the FM25B filter. This setup helps prevent sediment and hard water from impacting the FM25B's lifespan.
Installation Video Guide
For a comprehensive guide on installing an iSpring whole house water filtration system, please refer to the official installation video below. This video demonstrates the general process which applies to systems compatible with the FM25B cartridge.
Video: Official iSpring Whole House Water Filtration System Installation Guide. This video provides visual instructions for setting up your whole house water filter system.
Operating Principles
The iSpring FM25B filter utilizes catalytic media to effectively reduce iron and manganese from your water. This process does not consume the media, contributing to a longer filter life compared to traditional greensand filters.
- Iron Reduction: Reduces iron levels from a maximum of 3.0 ppm down to 0.01 ppm.
- Manganese Reduction: Reduces manganese levels from a maximum of 1.0 ppm down to 0.01 ppm.
- Flow Rate: Designed for high flow rates with a very low pressure drop. Expect up to a 5 psi drop at a flow rate of 8 gallons per minute (gpm).
- Operating Conditions: Stable performance within a pH range of 5.8 - 8.6 and a temperature range of 40 - 113°F (4.4 - 45°C).

Image: Clear water flowing from a faucet, illustrating the benefit of filtered water.
Maintenance
Regular maintenance, primarily filter replacement, is crucial for ensuring the continued effectiveness of your iSpring FM25B filter cartridge.
- Filter Lifespan: The FM25B filter typically lasts up to 50,000 gallons when treating water with a 3.0 ppm iron level, or approximately 12 months based on 200 gallons per day (GPD) usage. Actual lifespan may vary depending on water quality and usage.
- Replacement: Replace the filter cartridge when you notice a decrease in water flow or a return of iron/manganese symptoms (e.g., reddish-brown stains, metallic taste).

Image: A hand demonstrating the process of inserting a new filter cartridge into a water filter housing.
Troubleshooting
If you experience issues such as reduced water flow, persistent iron or manganese discoloration, or unusual tastes/odors after installing the FM25B filter, consider the following:
- Reduced Flow: This often indicates a clogged filter. Check if it's time for a replacement based on the recommended lifespan or if your water has unusually high sediment levels.
- Iron/Manganese Symptoms Persist: Ensure the filter was installed correctly and that your water's iron/manganese levels are within the filter's capacity. Very high concentrations might require additional pre-treatment.
- Leaks: Check all connections for proper sealing. Ensure O-rings are correctly seated and lubricated.
For further assistance, please refer to the Support section.
Specifications
| Feature | Detail |
|---|---|
| Model Number | FM25B |
| Product Dimensions | 6"D x 22"W x 6"H (4.5" x 20" cartridge size) |
| Item Weight | 8 Pounds |
| Material | Iron (referring to the reduction capability, not the filter material itself) |
| Product Benefits | Removes Iron and Manganese |
| Iron Reduction Capacity | MAX 3.0 ppm down to 0.01 ppm |
| Manganese Reduction Capacity | MAX 1.0 ppm down to 0.01 ppm |
| Feed Water Pressure | 20 - 100 psi |
| Pressure Impact | Up to 5 psi drop at 8 gpm flow rate |
| pH Range | 5.8 - 8.6 |
| Temperature Range | 40 - 113°F (4.4 - 45°C) |
| Filter Life | 50,000 gallons at 3.0 ppm iron level, or approx. 12 months @ 200 GPD |
| External Testing Certification | ANSI (tested by independent third party against NSF/ANSI standards) |
| Compatible Systems | iSpring WGB22BM, iSpring WGB32BM |
| UPC | 662425080076 |
Warranty and Support
iSpring is committed to providing high-quality products and excellent customer service. The FM25B filter is manufactured to comply strictly with FDA standards and is tested by an independent third party against NSF/ANSI standards for water quality, material safety, and structural integrity.
We offer lifetime free technical support from our U.S. local support team. If you encounter any problems with your water filter or have questions, please do not hesitate to reach out to us immediately. We are dedicated to helping you find solutions.

Image: A customer service representative wearing a headset, symbolizing readily available support for any inquiries.

Image: A flowchart illustrating the customer support process, from identifying an issue to receiving a solution.
For support, please visit the official iSpring website or contact their customer service directly. You can find contact information on the product packaging or the iSpring website.
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