Nelsen 18x65 Filter Unit

The Nelsen 18x65 Filter Unit steps up to commercial-grade filtration, delivering high-volume backwash-only treatment for demanding applications. With its large 18" x 65" tank and top-mounted Nelsen control valve, this system is built to handle the flow rates required by light commercial facilities, multi-bathroom properties, and other settings where standard residential units fall short. It provides a scalable foundation for serious whole-building water improvement.

This unit features a natural polyglass mineral tank and a stack distributor designed for the larger media volumes that bigger commercial tanks require. The stack distributor and gravel bed work together to spread water evenly across the full media bed, maximizing contact time and ensuring thorough backwashing of the entire bed. The included bypass valve makes it easy to take the system offline for inspection or media changes without interrupting the rest of the plumbing, an important convenience in commercial settings where downtime must be minimized.

Commercial Backwash Filtration

• 18" x 65" natural polyglass mineral tank for high-capacity service
• Nelsen C-Series EE 1" 3-cycle backwash filter valve, top-mounted
• Bypass valve included for maintenance and servicing
• Stack distributor with gravel bed for even, full-bed flow
• Substantial unit weight of approximately 203 lbs
• Filter media and plumbing connections sold separately

As a backwash-only system, it cleans itself by periodically reversing flow to purge accumulated particulate, reducing manual maintenance to occasional media replacement. Because the media is selected separately, the Nelsen 18x65 can be tailored to the specific challenge at hand, whether that is sediment, chlorine taste and odor, or another treatment objective. For contractors and facility managers specifying commercial water filtration, this Nelsen unit offers a proven, durable platform that, paired with the right media and plumbing connections, delivers cleaner water at the volumes commercial operations demand.

Proper installation and a drain line of adequate size will ensure backwash cycles run effectively, carrying flushed particulate away without restriction. With the right media selected for your water test results, this Nelsen platform delivers years of dependable service while keeping operating costs low and water quality high throughout the home. As a trusted Nelsen system paired with proven Nelsen control hardware, it brings professional-grade filtration within reach of homeowners and installers alike.