Activated Glass Media – Better Than Sand for Perfect Filtration

I’ve long thought that it was impossible to improve on the water quality delivered by our proprietary SRK HydroZone 3® system. As many will attest, it’s hard to describe the water’s pristine and invigorating qualities, and just as difficult to imagine it could be any better.

While that is perfectly true, at the same time it doesn’t mean as a water quality professional I am satisfied to stand pat. I’m always tinkering and experimenting, researching new approaches to improve water quality and looking for ways to fine tune and improve our HydroZone 3 system. My constant restless searching recently paid off in what I suspect might be a very big, industry-changing way.

Before I get into it, let me be perfectly clear that I’m not here to promote anyone’s product, but when something works to improve pool water quality as well as what I’m about to describe, I believe it’s worth letting others know so they can come to their own conclusions. With that caveat in mind . . .

What I Found – Alternatives for Improved Water Quality

As I’ve written many times before, I’m an avid proponent of the sand filtration method of pool water technology. Why that’s so is a long discussion, but for now suffice it to say that it’s the filtration media that, in my experience, has delivered the best results in terms of pool water quality and ease of maintenance.

I’ve also been long aware that there are sand replacement products that claim to improve the performance of sand filters. My results with sand filters have been so strong and consistent, I never gave much thought to alternative media, at least not until recently.

One of my good friends in the industry and my UV supplier, Roger Anderson, of If It’s Water, has been encouraging me to try out a product called Activated Filter Media (AFM) from a U.K.-based company called Dryden Aqua. Roger has been adamant that the product would be a great fit with our HydroZone 3 system, so I finally decided to see what his fuss was all about.

The product is an activated-glass media that’s manufactured in three grades that serve as a mirror replacement for a layered filtration bed. The idea is that metals in the glass are energized to create a catalytic effect, similar in some ways to a copper or silver ionizer. That means the filter becomes “bio-resistant” while also curtailing the formation of disinfection by-products (DPBs) such as trichloramines, the compound that generates the chlorine smell and causes eye and skin irritation, and trihalomethanes, a family of nasty compounds found in polluted natural waters and some public water systems, some of which are carcinogenic.

Because of the bactericidal action and reduction in DPBs, the company claims that AFM reduces the amount of chlorine needed to keep up with the sanitizing and oxidizing demand, reducing residuals to as little as a half-part per million. The concept is, in many ways, entirely congruent with our HydroZone 3 system, which is all about reducing chlorine levels by effective sanitization and oxidation via our finely tuned combination of ozone and UV. Having a filter that not only removes particulate but also works harmoniously with our system struck me as potentially a step forward.

To cut to the chase, when I tried it on my own pool at home, which is where I often first experiment with new products and techniques, I was impressed by the results. In water that is already a work of art, it became even more so. There’s an added polish and shimmer that I did not realize was possible. I have not tried any of the competing products on the market, so I have no basis of comparison, but with this one example, my eyes have been opened to the value of sand alternatives to further improve water quality.

Should You Consider AFM to Improve Water Quality?

I’ve learned a lot about the product and the company from Dryden Aqua’s U.S. representative, Sean McDermott. He explains it this way: “The pool industry has always used a kind of ‘shock and awe’ campaign when it comes to how water is chemically treated. We take a gentler more biological approach, where we’re reducing the chemical burden and increasing overall filter efficiency. The self-sterilizing action in the activated media prevents biofouling of the media, the structure of our glass particles prevents channeling. Where sand filters down to 20 microns at 8 gpm, all things being equal, the AFM product filters down to 4 ppm. Yet, because of the shape and structure of the glass and particle size distribution, it loads more evenly and stretches out the time needed between backwashing, ultimately using 50% less water.”

Clearly those are some powerful claims and I’ll leave it to the company to back them up with data and product performance testing. For my part, I can say that based on close observations over the past several weeks, everything McDermott is saying appears to be accurate.

I’m also fascinated by the company’s story, products, and philosophy. It’s named for Scottish inventor and visionary, Howard Dryden, PhD, who founded the company based largely on his research in molecular sieve ion exchange in zeolitic sand filtration systems for closed system aquaculture, and development of intensive aquaculture technology. The company produces not only the AFM product but also a host of others, including a flocculent, an AOP generating system, and a fascinating photocatalyst and chlorine stabilizer.

“Dr. Dryden is a visionary and one of the world’s leading experts in sustainable water treatment,” McDermott says. “Many of the solutions he developed were originally for treating water in large marine mammal exhibits, which is an extreme environment in terms of water treatment. He’s also developed a number of products for public water treatment, as well as aquaculture and aquarium applications.

“And,” he adds, “Dr. Dryden is a fierce marine environmental advocate and leader.”

Apparently, the product line has been wildly successful in Europe, where water quality standards are in many places far more stringent than in the U.S. If my experience is any indication, the company will do very well in North America and set new standards for pool water quality and the industry. For my part, it’s encouraging and inspiring to discover ways to improve on perfection.