Re-generating excitement: why indoor waterpark operators are so enthusiastic about regenerative media filter technology--and why you should be, too.(BOTTOM LINE)

Since the dawn of waterparks, public and private sector properties have relied upon high-rate sand filters for their water. But as waterparks become more popular and bather loads increase, many sand filters are being pushed to their limits, requiring costly backwashing nearly every day.

Cost issues aside, this has not been a problem for outdoor waterparks because air quality is not an issue and filtration systems usually can recover during the evening and inclement weather.

Indoor parks, however, are typically open 8 a.m. to 11 p.m.; weather is never a concern. And many parks operate at peak attendance from the time the doors open. So all mechanical components, including the filtration system, have to constantly contend with a workload that outdoor facilities experience only occasionally.

New products such as ultraviolet technology have helped to upgrade water and air quality in modern aquatics facilites. Variable frequency drives for pump motors have become more common to help control energy consumption. But the item that may have had the greatest impact on these indoor facilities is the regenerative media filter system.

The RMF system is not new, but its technology has recently been enhanced and redeveloped specifically to address the water-quality demands of indoor waterparks. With many favorable features, functions and benefits, the product has become the filter system of choice--particularly for parks with large bodies of water and high flow rates.

Traditional high-rate sand filters operate on the premise of "depth filtration," with soil particles being trapped in the bed of silica sand. When the differential pressure across the bed elevates to a value around 10 to 15 psi, backwashing is performed to remove the trapped particulate. The filter cycle then starts over.

RMF systems operate on the premise of surface filtration and incorporate a tremendous amount of filter area in a relatively small space. The internal components of the RMF systeminclude vertically supported "flex tubes." These tubes are composed of a high-strength, polyester-wrapped, stainless steel, spring-shaped frame and offer exceptional filter area. For instance, a 60-inch-diameter RMF includes 2,460 flex tubes with 1,760 square feet of filter area that can circulate nearly 3,000 gallons per minute. Comparatively, a 3,000 gpm sand filter system would conservatively offer 200 square feet of filter area.