DE NORA TETRA® advanced media filtration systems

Effective, efficient and reliable filtration systems.

DE NORA TETRA® filtration systems are effective treatment solutions for municipal and industrial water systems to ensure regulatory compliance.
With 1,300+ installations worldwide, including deep bed (denitrification filters) and drinking water filter underdrains, our proven DeepBed™ and Denite® technologies deliver reliable, efficient performance backed by 70+ years of expertise and global support.

The DE NORA TETRA® range includes:

The filter underdrain is a critical component for achieving reliable performance in gravity filters, whether in new installations or retrofits.
DE NORA TETRA® underdrains are designed to maximize efficiency, extend filter life, and reduce maintenance across municipal drinking water, desalination pre-treatment, and wastewater applications.

• Drinking water
  Our dual parallel lateral underdrains, including DE NORA TETRA U, LP, and Anchor-Rite® Blocks, ensure even distribution of backwash air and water, keeping filter media clean and improving filtration performance.
  They are easy to retrofit, resist uplift pressure, offer low operating costs, and require minimal maintenance.

• Wastewater treatment
  For heavily loaded wastewater, SNAP T® Block underdrains provide a non-clogging solution that handles oils, grease, and solids effectively. With customizable media, excellent backwash distribution, and simple installation, they deliver efficient cleaning, low operating costs, and long-term reliability, without moving parts.

It integrates suspended solids removal with biological oxidation processes, including nitrification and denitrification. This one-step solution enhances treatment efficiency while minimizing space requirements.
The rugged SNAP T® Block underdrain ensures consistent performance by preventing clogging and lifting, even in challenging biological applications.

• All-in-one treatment
  Denite® systems remove nitrogen, phosphorus, and suspended solids in a single step, using only a fraction of the space of traditional suspended growth systems - ideal for retrofits or space-limited sites.

• Aerobic solutions
  ColOX™, SAF, and NSAF filters efficiently handle BOD/COD oxidation and nitrification across diverse wastewater streams.

• Flexible design
  Modular prefabricated or on-site builds accommodate various media types, giving you process flexibility and dependable performance.

It combines the power of ozone with biologically active filtration to deliver advanced, reliable water treatment for municipal and water reuse applications.

Ozone first breaks down challenging organic and inorganic pollutants, and the biologically active filter continues the treatment, removing residual contaminants and disinfection byproducts while producing a biologically stable effluent.
This combination offers several practical advantages.
Smaller ozone systems reduce both equipment and energy costs, while the process eliminates the need for expensive upstream RO or UF membranes.

The BAF also targets bromate, aldehydes, NDMA, and assimilable organic carbon (AOC), reducing the risk of downstream biofilm growth. With proven results, such as significant TTHM reductions in municipal applications, the DE NORA TETRA® solution delivers high-quality, safe water reuse in a compact, efficient, and cost-effective system.

Discover our media filtration systems.