Dryden Aqua Healthy Swim AFM Grade #3 (Gravel Used for Under Drain) Glass Filter Media 55 LB Bag

Dryden Aqua Healthy Swim AFM® Grade #3 (Gravel Used for Under Drain) – Activated Glass Filter Media (55 lb Bag)

Premium Bio-Resistant Gravel Replacement for Pool & Commercial Filtration Systems

Dryden Aqua Healthy Swim AFM® Grade #3 is a high-performance, activated glass filter media specifically engineered to replace traditional gravel in sand filter underdrains. Manufactured from recycled green and brown glass, AFM® is biologically activated to prevent bacterial growth, reduce chloramine formation, and deliver superior water clarity for years.

Unlike standard glass media or sand, AFM® Grade #3 provides unmatched mechanical and electrostatic filtration, making it the ideal foundation layer for professional pool filtration systems.

What Is AFM® (Activated Filter Media)?

AFM® (Activated Filter Media) is a bio-resistant, self-sterilizing filter media made from carefully selected green and brown recycled glass. Through a proprietary 3-step activation process, its surface area is increased by up to 300x, enabling it to trap finer particles, inhibit bacterial colonization, and prevent channeling.

AFM® is not glass sand—it is a highly engineered filtration solution designed for long-term, high-efficiency performance.

Grade #3 Application

• Grade #3: Replaces traditional gravel in sand filter systems (underdrain layer)

• Grade #1: Replaces #20 silica sand (sold separately)

AFM® Grade #3 provides a stable, contamination-resistant base layer that improves overall filtration efficiency and water quality.

Key Benefits of AFM® Glass Filter Media

✔ Filters at least 2x better than sand
✔ Bio-resistant surface prevents bacterial growth
✔ Reduces biofouling, coagulation, and channeling
✔ Produces crystal-clear water
✔ Lowers chlorine consumption
✔ Reduces harmful disinfection by-products (DBPs)
✔ Minimizes chloramine odors and irritation
✔ Reduces risk of pathogens like Legionella, Pseudomonas, and Cryptosporidium
✔ Sustainable and eco-friendly (made from recycled glass)
✔ Never needs recharging or replacement
✔ Long-lasting performance for many years

Why AFM® Outperforms Sand & Other Glass Media

1. Proprietary Activation Process

AFM® undergoes a unique 3-step mechanical and chemical activation process. This activation gives AFM® its bio-resistant properties and superior filtration capability—something standard glass or sand cannot achieve.

2. Specialized Raw Materials

Only green and brown glass is used. The natural metal oxides responsible for the glass color create a negative charge that attracts fine contaminants. This electrostatic charge is enhanced during activation.

3. Advanced Manufacturing

Dryden Aqua is a filter media manufacturer, not a recycling company. Every particle is precision-shaped and polished:

• No sharp edges

• No filter damage

• No user injury

• Optimized hydraulic performance

4. Proven Filtration Efficiency

Independent laboratory tests (IFTS, France) confirm that AFM® filters particles over 4x smaller than sand and outperforms all competitive glass media.

Self-Sterilizing & Regenerative Technology

The activated surface of AFM®:

• Prevents bacteria mud-balling

• Stops coagulation

• Eliminates wormhole channeling

• Adsorbs pollutants like activated carbon

• Recharges naturally through backwashing—no chemicals required

Sustainable, High-Performance Pool Filtration

AFM® supports a healthy, ecological, and economical pool water treatment strategy. It reduces chemical demand, extends filter life, and improves swimmer comfort.

Trusted in over 200,000 pools worldwide, AFM® is the professional standard for next-generation filtration.

Where Can You Use AFM®?

AFM® Grade #3 can be used without any system modifications in:

✔ All sand and glass sand filters
✔ Natural and bio pools
✔ Saltwater pools
✔ Systems using any oxidation method
✔ Hot and cold water applications

Product Specifications

• Product Name: Dryden Aqua Healthy Swim AFM® Grade #3

• Media Type: Activated Glass Filter Media

• Function: Gravel replacement (underdrain layer)

• Bag Weight: 55 lbs

• Material: Recycled green & brown glass

• Technology: 3-stage activated, bio-resistant surface

Dryden DAISY®

Additional Information

AFM FAQ Sheet

AFM Brochure

AFM Brochure

SDS Sheet