If you thought pool filtration was a yawn, think again.

At the 2006 International Pool & Spa Expo in Las Vegas, innovations abounded. Cartridge filters with enhanced antimicrobial qualities were unveiled. A filter merging diatomaceous earth and cartridge design was introduced. Sleek, high-performance sand filters replaced the clunky models of the past. And alternative mediums seemed more readily available.

“We’re seeing better and better equipment all the time,” says Al Rizzo, owner of Rizzo Pools in Newington, Conn. “Pumps and filters are lasting longer and they’re more powerful.”

Filters certainly have matured as a product category. The unit itself is larger, quieter and highly automated. Despite a number of challenges and stubborn regional variations, filters and filter media continue to forge forward and embrace emerging technologies. Here, Pool & Spa News explores four trends influencing the field of filtration.

1 Sales are steady.

Sales of filters and filter media generally parallel those of swimming pools and spas. As a result, filter sales dipped recently as pool sales slowed in many of the country’s leading markets.

Sand filter sales fell by a marginal 2.6 percent from 2004 to 2005, according to Veris Consulting, LLC, in Reston, Va. In the same time period, DE filters dropped 4.2 percent. And cartridges took the biggest hit, with unit sales falling 12.2 percent — due mostly to poor weather in the Northeast and Midwest.

“[In 2005], filters were down slightly, 3.4 percent for the industry overall. Those figures were probably skewed by being a tough market for aboveground pools because of the weather,” says Mark Normyle, director of marketing for pumps and filters at Hayward Pool Products in Elizabeth, N.J.

Despite what the numbers indicate, cartridge continues to lead in popularity. “Cartridge is absolutely the highest growth category of filters,” says David Nibler, vice president of marketing and business development at Jandy in Petaluma, Calif. “Sand is still the leader, but it’s being reduced,” Nibler adds. “Cartridge is overtaking it very quickly.”

Normyle believes that the market in 2006 was likely more promising. “I would expect to see an up year, especially with the larger aftermarket in replacements,” he says.

2 Units are grandiose.

When it comes to filters, service technicians and customers prefer ease of maintenance. As a result, larger sizes are the standard today. They make replacement and warranty work easier, while remaining aesthetically pleasing.

“There’s a focus on efficiency from the standpoint of fluid dynamics,” Normyle says. “There’s a trend toward larger plumbing and sizes, so you oversize the filter to maintain it less. In the case of an element filter, you clean the element less frequently.”

Other manufacturers agree. Nibler says that while filters may be larger, they have the same footprint. “We are seeing pressure from the builders to plumb the same equipment on a smaller pad,” he says.

In some cases, cartridge filters up to 600 square feet in size are fitting the same niche as a 150-square-foot unit. The larger product is simply taller. “That’s definitely the trend — bigger is better,” says Jeff Fausett, president/CEO of buying group Aquatech Corp. in Huntington Beach, Calif. “It’s really about making the maintenance side easier. Now the technicians can reach into the equipment from the side to service the equipment.”

Do-it-yourself customers also are sold on the minimal cleanings associated with big filters. “Some customers can clean the pool twice a year, which they love,” says Russ Watters, owner of Watters Aquatech Pools & Spas in Las Vegas. He includes a mid-size cartridge filter standard with his pools, but offers upgrades to larger ones.

3 Regional variations thrive.

Thanks to a number of environmental and legislative issues, regional preferences still dominate the filtration spectrum. For instance, DE continues to remain a favorite in the East. In the West, however, its popularity has waned slightly.

“That’s driven by two things. Certainly, you hear more about droughts in the West, and that’s when they start frowning on backwash issues,” says Kevin Potucek, vice president of marketing at Hayward. “Also, you typically run into a higher level of environmental consciousness, and for those concerned about DE’s impact, that’s a factor.”

Potucek believes this same consciousness is infiltrating some East Coast markets, particularly in Florida. “There’s certainly awareness in many bay cities about DE going into the sewer systems that could end up in the water. That includes places such as Tampa, Chesapeake Bay and even San Francisco.”

As a result, cartridge sales have overtaken DE figures. That’s a shame, Rizzo says. He believes that DE’s finer filtration is of greater benefit to the homeowner.

Unfortunately, city health departments often don’t understand pool filtration.

“What’s happening in my area is that they’re forcing the switch to cartridge even though DE has been used for years in the dry-cleaning industry without needing separate septic tanks or lines,” Rizzo says.

Similar events are unfolding in Orange County, Calif., as well. The region recently legislated that every pool filter — regardless of media — requires a backwash line to the sewer, builders there say.

“Almost all of our residential installations are cartridge … and you can’t backwash a cartridge filter,” says Vanz Steimle, distribution manager of California Pools Inc., a Pool & Spa News Top Builder in West Covina, Calif. “We have a long way to go to educate our cities and governments.”

Despite the advantages of using cartridge filters and the clear growth they’ve experienced, sand still reigns in sheer volume of product sold and installed. It’s especially useful for commercial pools, builders say.

“I don’t think cartridge is overtaking sand,” says Carlos Del Amo, vice president of marketing and product development for Pentair Water Pool and Spa in Sanford, N.C. “There are regions where you could reduce the price of a cartridge filter by half, and it still wouldn’t be accepted. You will always have regions that stick to what is standard in their area.”

4 The future holds innovation.

Down the road, manufacturers believe the filter can only get better. For one, enhancements and product designs continue to emerge. In addition, builders can expect to see an increase in automation and the use of alternative media.

Most of the latest designs seek to deal with the legislative issues surrounding backwashing without compromising quality. “For instance, many are installing sand filters, but using zeolytes as an alternative medium,” Fausett says. “That’s taken off in the last couple of years. It’s cropped up in Texas and Oklahoma.”

Another option is Pentair’s recently unveiled filter, which combines cartridge and DE technologies. “It gives DE clarity with a cartridge filter,” Del Amo says. “It’s a DE filter with four cartridges, so if you want to clean the filter, you can do it without having to backwash.”

Builders are enthusiastic about the concept. “That’s a move in the right direction,” Rizzo says. “It sounds fantastic, [but] I still want to make sure that it’s the right product and it fits all of our requirements.”

Meanwhile, other manufacturers are wary that hybrid products won’t deliver value to the homeowner. “We’re continuing to test the new technologies, [but] we haven’t seen any of them pan out yet. There is no panacea out there,” Potucek says.

Still, another significant advance has emerged in the area of high-end sand filters. “They can read their own filtration levels,” Rizzo says. “When the pressure rises, it can sense it and automatically initiate backwash. In the future, everything will be automatic and internally sensored so the homeowners can tell you when it’s time to change the cartridge or backwash.”


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