Case Studies

Proven on the Frontlines

OneFlow®, with template-assisted crystallization (TAC) technology, has been tested in real-world applications and been proven to continually outperform other scale remediation processes. Listed below are just a few examples.


“Since we’ve installed the OneFlow systems, scale buildup hasn’t been an issue.”
-Jill Kidd, Pueblo City School Director Food Services

Pueblo Colorado School District

Solves Hard Water Woes

  • Industry: Education
  • Category: Water Quality
  • Location: Pueblo, CO
  • Installation: OneFlow® Anti-Scale System

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CUSTOMER: Pueblo City School District, Pueblo, Colorado.
SCOPE: Commercial kitchens in the school district needed better water treatment system.
CHALLENGE: Due to the extreme hardness of the water, scale build-up had become an extensive problem on combi ovens, causing maintenance nightmares.
SOLUTION: Point-of-use OneFlow® anti-scale systems installed.
RESULTS: Elimination of scale build-up problems.

Scale build-up in the combi ovens in all the district’s kitchens was so bad that at times lunch was served late. After replacing the ovens several times, and trying a variety of treatment systems, the school’s maintenance department was seeing little to no improvement in the scale build-up problem.

Jill Kidd, director of food services at Pueblo City Schools contacted Paul Gradishar, president of Grady’s Restaurant and Bar Supply in Pueblo for help. Within a week, Gradishar supplied one dozen point-of-use OneFlow anti-scale systems that use template assisted crystallization technology to the high school’s maintenance department.

"Since we’ve installed the OneFlow systems, scale buildup hasn’t been an issue," said Kidd. Hot meals are now prepared and delivered on time, and our maintenance staff that had been tasked with fixing scale issues are now free to handle other projects throughout the facility.

According to Kidd, the school’s maintenance department had no trouble installing the units. One thing was certain: they were happy not to deal with scale problems on a daily basis.


“The OneFlow anti-scale systems are easy to install – PVC in, PVC out; no pumps, meters, valves, etc.”
-John Lipka of E. H. Whitson Plumbing

Anthony’s Coal Fired Pizza

OneFlow® Saves Dough

  • Industry: Food Service
  • Category: Water Quality
  • Location: Eastern US
  • Installation: OneFlow® Anti-Scale System

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CUSTOMER: Anthony’s Coal Fired Pizza, gourmet pizza chain.
SCOPE: Protect restaurant equipment from effects of hard water in a cost effective way.
CHALLENGE: Hard water treatment for restaurant locations too expensive, and the ever-increasing amount of salt could potentially change pizza dough flavor and texture.
SOLUTION: Light Commercial Watts OneFlow anti-scale systems installed at pizzeria locations throughout Eastern US.
RESULTS: OneFlow system eliminated the use of chemical additives, doesn’t create waste water and results in zero pollution while minimizing installation and maintenance costs. It also uses zero electricity.

Anthony Bruno, founder of ACFP was dealing with extremely hard water issues in one of his franchise locations in south Florida.

Since the salt-based softeners currently in use were only reducing scale marginally, the only option was to continually increase the salt setting or regeneration cycle. For the pizzeria, the concern was that higher salt levels would change the flavor or texture of the pizza dough. The restaurant hired E.H. Whitson Plumbing to find a solution

After talking with Rick Sharp at Lion Plumbing Supply, and Rob Nehls, at the rep firm, Harry Warren Inc., one OneFlow anti-scale system which uses template assisted crystallization technology was specified to handle all four of the problems that ACFP restaurants were facing; salt use, equipment rental and service, high utility costs and ineffective scale prevention.

"The OneFlow anti-scale systems are easy to install," explained Lipka of E. H Whitson Plumbing Company. "PVC in, PVC out; no pumps, meters, valves, etc. Limited maintenance is required; systems require media replacement every three years."

The people at Anthony’s were thrilled with the results of the first two OneFlow installations, and decided right after the meeting to replace the softeners at each of the 40+ pizzeria locations.


“With environmentally-friendly scale prevention technology, we were able to give the homeowners’ peace of mind.”
-Cartwright Plumbing, Heating and Cooling Senior Technician Mario Larranaga

Cartwright Plumbing, Heating and Cooling

OneFlow® Solves Multiple Water Woes

  • Industry: Residential
  • Category: Water Quality
  • Location: Santa Fe, NM
  • Installation: OneFlow

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CUSTOMER: Residential customers in the Santa Fe area.
SCOPE: Reduce scale due to water hardness level for domestic supply including water heaters and rooftop swamp cooler.
CHALLENGE: Improve water quality throughout the homes they serve to eliminate ongoing problems with scaling of cooling system’s hydration pads.
SOLUTION: Watts OneFlow® anti-scale systems
RESULTS: After OneFlow® installation two years ago, the pads have remained in perfect working order.

Some of the world’s most radical temperature changes occur in northern New Mexico. Most homes there are equipped with an evaporative or “swamp” cooler, an energy-wise approach to home cooling in arid regions. The problem: the equipment is not fond of scale.

This adobe home gets water from the ground with 8 grains of hardness/gallon. The owners spent $300/month replacing calcium-clogged swamp cooler pads. Mario Larranaga, Sr. Technician at Cartwright Plumbing, Heating and Cooling based in Santa Fe said, “Even with substantial water softening, the pads would get so covered in scale that the fan wouldn’t even blow air through the media.”

Larranaga tried different salts, and even a different softener, but the systems kept scaling up. Solution: Cartwright’s turned to Watts’ OneFlow® anti-scale systems. “We like OneFlow® because it doesn’t add chemicals to the ground water, and isn’t carcinogenic,” said Laranaga.

It’s been two years since the swap-out, and the pads haven’t been changed once.


"Fort Sill will reap the benefits of zero water discharge and no salt expense for years to come."
-National sales manager of water treatment products at Watts Water Technologies Steve Callahan

Fort Sill United States Army Base

OneFlow® Goes to War with Ultra-Hard Water

  • Industry: Government
  • Category: Water Quality
  • Location: Lawton, OK
  • Installation: OneFlow Model Model # OF1665-75 x12

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CUSTOMER: Fort Sill United States Army Base.
SCOPE: Eliminate use of chemical additives, reduce water discharge and wastewater and use a salt-free system if possible.
CHALLENGE: Water at Ft. Sill measures 27 grains of hardness per gallon. Each of the barracks experience domestic water use spikes up to 632 GPM.
SOLUTION: Watts OneFlow® Anti-Scale Systems, Model #OF1665-75 x 12.
RESULTS: Treatment a success; zero water discharge + no salt expense.

In the 1970s, Initial Entry Training (IET) “starship barracks,” were constructed on Army bases nation-wide, including Fort Sill. The facilities acquired the nickname because they’re completely self-contained with living quarters, classrooms, mess halls and latrines all under one, star-shaped roof. Many of the starship barracks are being renovated, chiefly to reduce energy consumption. Each barracks holds 500 troops – at that number; high-quantity water use is inevitable – with spikes up to 632 GPM.

Hard water has plagued maintenance crews at Ft. Sill since the addition of indoor plumbing. While water is considered hard at 10 grains of hardness per gallon, Ft. Sill’s water measures in at 27.

Archer Western Contractors knew the water treatment system must handle a huge volume while being cost effective. With these parameters, they chose the Watts OneFlow® anti-scale system. The project called for 12 OneFlow® tanks and four and eight-inch Watts model 957 RPZ backflow preventers to protect the domestic water system. Strainers installed upstream of the RPZs help keep debris from getting into the OneFlow® system and backflow preventers.


"A couple months ago, we had to replace the motor on one of our domestic pumps, and when the contractors took the system apart it showed no sign of scale inside, at all."
-Crowne Plaza La Concha Chief Engineer Daniel Betlewicz

Crowne Plaza La Concha

OneFlow Proves a "Perfect Fit" in Iconic Key West Hotel

  • Industry: Hospitality
  • Category: Water Quality
  • Location: Key West, FL
  • Installation: OneFlow Model # OF1665-75 x4 (300 GPM)

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CUSTOMER: Crowne Plaza La Concha, located on Duvall St. in the heart of Key West, was built in 1926. Rich in history, it has been home to famous writers and jet setters. Today the popular hotel books rooms year-round at 90% of capacity.
SCOPE: The hotel’s goal was to control scale in its seven-story hotel, including 160 guest rooms, pool, laundry facilities, three bars and a restaurant.
CHALLENGE: Reduce unscheduled maintenance and increase the life of capital equipment.
SOLUTION: Watts OneFlow® Anti-Scale Systems, Model # OF1665-75 x4 (300 GPM).
RESULTS: In addition to a 90% space footprint reduction, the hotel has reported no visible scale in fixtures and capital equipment since its installation in 2007.

Keeping water flowing freely and safely for guests is a priority for any hotel, but for the Crowne Plaza La Concha, in the heart of Florida’s Key West, hard water and scale buildup were serious concerns. Key West receives the bulk of its water from a pipeline which pumps notoriously hard water from the Biscayne Aquifer in the Florida Everglades. "You could visibly see the scale," says Chief Engineer Daniel Betlewicz, "On the sinks, but especially in the back of the house…and in the laundry area where water was used on a daily basis." Maintenance on capital equipment, such as water heaters, had to be done regularly, and opening them up, the La Concha engineers would find clumps of scale build up that needed to be scraped out, wearing on and potentially damaging equipment over the long-term.

Betlewicz describes the decision to go with OneFlow from Watts as a "no-brainer". In addition to it scale control and low water waste, it was just the compact solution the retrofit needed. "This system actually fits my boiler room," the Chief Engineer explains. "We’ve got limited space because the building is old. This system is very compact. It’s just four tubes…a perfect fit."

Five years later the system is viewed as a huge success, saving La Concha time and money. "This is a good solution for every hotel," says Betlewicz. "No one calls me for any scale problems, anymore. A couple months ago, we had to replace the motor on one of our domestic pumps, and when the contractors took the system apart it showed no sign of scale inside, at all. Even the contractors were surprised, you know, cause there’s usually something. And we have no problem with water heaters or anything. We were pretty happy because I was expecting something, you know…and it was clean."

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"We’re delighted with our effort to become sustainably certified in the vineyards…(it) is a real boost to our sense of environmental responsibility."
-Evelyn Pool, Hahn Family Winery

Hahn Winery

Environmentally-Conscious Family Vineyard Tackles Scale

  • Industry: Hospitality
  • Category: Water Quality
  • Location: Monterey, CA
  • Installation: OneFlow Model # OF1665-75 x2 (150 GPM)

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CUSTOMER: With their location in the Santa Lucia Highlands overlooking the Salinas Valley, Hahn Winery offers wines which are among the finest in the region.
SCOPE: Treat well water used for heat cleaning and sterilization of fermenting barrels and bottles.
CHALLENGE: Hahn Winery’s goal was to ecologically eliminate chemicals, salts and waste discharge, while ensuring the highest quality water for its operations.
SOLUTION: Watts OneFlow® Anti-Scale System, Model # OF1665-75 x2 (150 GPM total).
RESULTS: Less costly up front, the solution is also estimated to save the facility nearly 70% in operating costs, mostly in salt and water purchase and discharge.

When the Hahn Family Winery recently sought out an effective and economical water treatment system to replace their previous salt-based water softener, environmental responsibility was a critical factor.

"With Hahn Winery’s move to become more ecological, we looked at every facet of our environmental stewardship", said Hahn spokesperson Evelyn Pool. "Water treatment was an important part of that puzzle. We’re delighted with our effort to become sustainably certified in the vineyards. Eliminating salt-based softeners while adding new [TAC] scale prevention is a real boost to our sense of environmental responsibility."

The OneFlow solution chosen by the winery requires no water-consuming discharge while providing hard water scale protection. The scale prevention media operates catalytically without salt or chemicals and does not produce a waste stream. "The [TAC] scale prevention is effective at preventing more than 98% of the scale produced by the winery’s hard water," said Watts National Sales Manager Stephen Callahan. "The only maintenance required on the system is a simple media replacement after two or three years of service." That means the Hahn Family Winery can enjoy the fruits of environmental responsibility through their use of salt-free water treatment and still meet their goals for an economical solution to hard water.


"With…very reliable, smart [OneFlow] technology, we’re able to meet [the] challenge and also to be a great deal more conservative with our natural resources."
-Frank Young, Utah Valley University

Capitol Reef Field Station

Environmental Research Station Battles Epic Hardness

  • Industry: Education/Science
  • Category: Water Quality
  • Location: Central Utah
  • Installation: OneFlow Model # OF1465-50 (50 GPM)

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CUSTOMER: A solar-powered village in central Utah, Capitol Reef is a place for researchers to study the natural and cultural history of the area. The facility is a joint effort of Utah Valley University and the U.S. National Park Service.
SCOPE: The site consists of two dormitories, a multi-purpose building, site manager’s home and maintenance building—all "off-the-grid" and resource-challenged.
CHALLENGE: Address astronomical (86 GPG) hardness levels in the park’s water.
SOLUTION: Watts OneFlow® Anti-Scale System, Model # OF1465-50 (50 GPM).
RESULTS: The site has been able to meet the hard water challenge, while being conservative with natural resources, avoiding the need for electricity and producing zero waste water or chemical waste.

Nestled into a canyon fold within a 378-square mile national park, the Capitol Reef field station is surrounded by vivid, red and white rock formations. Centuries ago, native Indians named the area "land of the sleeping rainbow." Every living organism inside the park is well adapted to the desert climate, making the most out of seven inches of annual precipitation. The few human inhabitants have learned to do the same: conserving natural resources and creatively solving problems that arise from the beautiful, but harsh, landscape.

One such problem is hard water—very hard water. Plumber Jared Anderson measured samples there at an exceptionally hard 86 grains of hardness per gallon. "That’s all but unheard of—even in this area," said Anderson. Water is considered hard at 1 GPG, and anything above 18 GPG is considered "extremely hard", which can cause harmful mineral scale build up in capital equipment. In addition to a harsh environment, the research site has limited electrical power from the solar array that powers it and the park service had strict requirements that forbade distribution of harmful sodium or other chemical discharge into the local ecosystem.

The water at the Capitol Reef Field Station is also high in sulfate and ferrous iron, so OneFlow was installed as part of a complete water system that included pre-filtration, macro and micro filtration, a nanofilter and an inline chlorine injection device. "Harvesting water in the desert is a challenge," said Frank Young, senior director of planning and development at UVU. "But with […] some very reliable, smart technology, we’re able to meet that challenge and also to be a great deal more conservative with our natural resources."


"The system has the desired small footprint and does not use any expensive or high-maintenance chemicals."

Quisling Terrace Apartments

Historic Apartment Residence Chooses OneFlow® Solution

  • Industry: Residential
  • Category: Water Quality
  • Location: Madison, WI
  • Installation: OneFlow Model # OF1465-50 x2 (100 GPM)

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CUSTOMER: 60-unit Apartment Residence in Mansion Hill district of Madison, WI.
SCOPE: Scale prevention system to protect domestic water heaters, valves and plumbing fixtures within a historic apartment complex.
CHALLENGE: To prevent damage of equipment from extremely high (30 GPG) hardness levels in Madison City Water.
SOLUTION: Watts OneFlow® Anti-Scale System, Model # OF1465-50 x2 (100 GPM).
RESULTS: OneFlow protects water heaters, valves and fixtures from hard water scale build up where the previously-installed scale inhibiting device had failed.

Tucked away in the Mansion Hill Historical District of Madison, Wisconsin, the Quisling Terrace Apartments boasts a classic exterior and classy interior, describing itself to prospective residents as "a home you will be proud of." In order to ensure that class and pride extended to the quality of its water, the apartment complex set out in 2007 to find a water quality solution that would protect domestic water heaters, valves and plumbing fixtures from the effects of extreme hard water.

A familiar Madison landmark built in 1890, the Quisling Terrace was originally a house, but was successively converted into an apartment building and then a midcentury health clinic. In 2000 it was renovated back into a sixty unit affordable-housing apartment building. Though the building did include an original scale inhibiting device, it was not equal to the task of dealing with the 30 grains per gallon of hard water minerals. Though its compact size and low cost met requirements, the system did not effectively stop scale build up and corrosion. The complex had to replace eleven water heaters over seven years and had numerous complaints from residents about lime and scale on fixtures.

Looking for a similar low-cost, compact solution that would be effective in preventing scale, manager Kat Gallagher chose the OneFlow Scale Control system. Overnight, the complaints from tenants ceased. So, too, did maintenance and service requirements. Further, the system has the desired small footprint and does not use any expensive or high-maintenance chemicals. It has operated continuously and without complaint since its installation in December 2007.


"The heater was opened to find no new scale, and the older scaled elements had a reduction of approximately 90% of the original scale build up."

San Bernardino Sheriff’s Dept.

After Rigorous Trial, OneFlow® Defeats Scale in Correction Facility

  • Industry: Law Enforcement/Institution
  • Category: Water Quality
  • Location: San Bernardino, CA
  • Installation: OneFlow Model # OF817-8H x2 (16 GPM)

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CUSTOMER: Primary booking facility for the police and sheriff stations in California’s east valley area, housing and feeding up to 850 federal and county inmates daily.
SCOPE: Protect a six-element booster heater that heats untreated incoming city water serving the kitchen of a regional prison facility.
CHALLENGE: To prevent damage to water heater from high (9 GPG) hardness levels in the city water.
SOLUTION: Watts OneFlow® Anti-Scale System, Model # OF817-8H x2 (16 GPM)
RESULTS: After 90 days of the OneFlow system being in operation, no new scale build up was found and a reduction of 90% of the original scale was removed from the older scaled elements.

Originally opened in 1971, San Bernardino’s Central Detention Center (CDC) is the primary booking facility for the police and sheriff stations operating in the east valley area. It currently houses approximately 330 federal and 600 county inmates. CDC also hosts a Juvenile Intervention Program for Kids (13-17 year olds) at risk.

A recent federal grant and partnership with the U.S. Marshal’s Service allowed the CDC to retrofit and upgrade its facility. In addition to new paint, furniture, metal detectors, and security camera system, the Sheriff’s department also conducted a complete remodel of their kitchen. Part of that project involved tackling the area’s water hardness problems, which was 470 parts per million total dissolved solids and 9 grains per gallon of hardness. Their primary concern was protecting the Hubbell Booster Water Heater in the facility’s kitchen. Within only three months of installation—with no water treatment—the six elements inside the heater were already requiring replacement due to scale build-up.

Unsure about gambling on a new technology, the department chose to conduct a ninety day trial period to assess OneFlow’s effectiveness. The test involved replacing three of the six elements with new elements and leaving the other three scaled elements in place. "It was a huge success," said Watts National Sales Manager Steve Callahan. "The heater was opened to find no new scale, and the older scaled elements had a reduction of approximately 90% of their original scale build up." The Sheriff’s Department was convinced that OneFlow technology is a viable alternative to traditional water softening systems, and they are currently evaluating their other facilities for applications to use this technology.

LA Live

Super Complex Finds Streamlined Solution to Hard Water

  • Industry: Hospitality
  • Category: Water Quality
  • Location: Los Angeles, CA
  • Installation: OneFlow Model # OF1665-75 x12 (900 GPM)

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CUSTOMER: L.A. Live is an entertainment and residential complex in downtown Los Angeles, adjacent to the Staples Center.
SCOPE: The centerpiece of the district—which includes sports, broadcasting, museum, entertainment and dining venues—is a 54-story, 1,001 room two-hotel hybrid tower that contains both an 879-room JW Marriott hotel and a 123-room Ritz-Carlton hotel. Top floors of the building hold 224 Residences at the Ritz-Carlton condominiums. The goal of this project was to provide both hot and cold water scale control in the Ritz-Carlton side of the tower.
CHALLENGE: Because the original specifications called for only hot water scale control, and there were already space constraints in the mechanical room, treatment for both hot and cold water would require a solution with a much smaller footprint. Additionally, the existing system could not adequately correct for pressure issues that more traditional water softeners would cause.
SOLUTION: Watts OneFlow® Anti-Scale Systems, Model # OF1665-75 x12 (900 GPM total).
RESULTS: The OneFlow system was a significant space savings over the original, while doubling the capacity to accommodate both hot and cold water. Since its installation in March of 2010, LA Live has had no scale related issues.

Embassy Suites Hotel

Wine Country Hotel Strikes Perfect Balance to Avoid Scale

  • Industry: Hospitality
  • Category: Water Quality
  • Location: Napa, CA
  • Installation: OneFlow Model # OF1665-75 x3 (225 GPM)

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CUSTOMER: The Embassy Suites Napa Valley hotel is located in the heart of Napa and Sonoma Wine Country, conveniently located near historic downtown Napa.
SCOPE: The 205-room hotel, situated on seven acres of beautifully landscaped grounds, is also home to the Grille 29 Napa restaurant.
CHALLENGE: Embassy Suites needed to address moderately high (5 GPG) hardness levels in their water. Their existing water softener for the hot water supply failed and needed to be replaced. The hotel was looking for a more economical solution to replace their water treatment system.
SOLUTION: Watts OneFlow® Anti-Scale Systems, Model # OF1665-75 x3 (225 GPM total).
RESULTS: After two months of OneFlow service, the hotel was already happy with its cost savings. The Chief Engineer also reported guest room sinks and faucets with visibly less scale build up. In addition, a boiler inspection report read, "No scale or any other types of deposits on internals of heat exchanger."

Caesars Windsor Hotel & Casino

Hotel Bets, Wins Big as OneFlow Prevents Humidifier Scale

  • Industry: Hospitality
  • Category: Water Quality
  • Location: Windsor, Ontario
  • Installation: OneFlow Model # OF844-12 x12 (144 GPM)

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CUSTOMER: This four-diamond hotel in downtown Windsor, Ontario—with 758 guestrooms and a 100,000 square foot state-of-the-art convention center—prides itself on providing an "essence of indulgence, comfort and luxury" in "masterfully-appointed guestrooms and suites."
SCOPE: Provide scale control for 21 humidifiers that support one of two hotel towers and supply water for the hotel kitchen.
CHALLENGE: Prevent scale build up on Nortec ACS7W humidifiers from high (8 GPG) hardness levels in the city water.
SOLUTION: Watts OneFlow® Anti-Scale Systems, Model #OF844-12 x12 ( 144 GPM).
RESULTS: In a comparative analysis between a humidifier treated with the OneFlow system and an equal capacity humidifier without, after 300 operating hours there was no scale build up on the heating elements and considerably less scale formation on the walls and bottom of the treated unit. Caesars Casino decided to install OneFlow units in front of all 21 humidifiers in the west block of the building as well as the supply water for the kitchen. The OneFlow system has eliminated water-related scale issues and saved the customer money in both maintenance and energy costs.


Before OneFlow – 300 hour operating time

  • Hard scale accumulation on humidifier walls and element
  • Cleaning unit would typically take 2 employees 1.5 hours


After OneFlow – 300 hour operating time

  • Soft scale accumulation on the bottom of the unit only, easily wiped away with a cloth
  • Element was clear of any hard scale build-up, reducing maintenance downtime by 90%