ASK THE EXPERTS | Pool Perfect
Area experts look at the factors behind the recent taste for saltwater pools
Saltwater pools have taken off in the last few years to become the fastest growing technology in new pool installation and are quickly winning converts. You’ll often hear it said that the customer doesn’t have to be sold on the system – they show up and demand it.
Just don’t expect the water in a saltwater pool to bear much resemblance to a dip in the ocean: Although it’s saline, salt concentration in pools ranges from 3,000 to 4,000 parts per million, compared to 40,000 or 50,000 parts per million in the open ocean. And while some customers may convince themselves that they can taste the salt, that’s rarely the case. Saltwater pools are even less salty than human tears. What you will be aware of, however, is the luxurious silkiness of the soft water and the freedom from bloodshot, stinging eyes.
Chlorinated pools may seem more complicated than saltwater pools, but it’s not exactly rocket science. They work on an erosion feeder system, adding chlorine to the pool by the erosion of chlorine pucks as the water circulates. Homeowners must monitor the pool constantly, guarding against spikes and making sure that summer storms don’t weaken the chlorine levels, and of course shocking the pool with concentrated infusions of chlorine every so often – a reliable source of stinging eyes.
Saltwater pools also disinfect the water with chlorine – that’d be the Cl part of salt’s NaCl molecule – albeit in a comparably diluted concentration. The system itself works somewhat differently than a chlorine puck system, however. A generator uses a form of electrolysis rather than erosion to break water molecules into hydrogen and oxygen. Salt-chlorine generators create chlorine when the water passes through electrolytic plates (cathode and anode), which separate the salt molecule to form the sterilizing sodium hypochlorite, or chlorine.
Yes, you read that correctly. Chlorine. A saltwater pool is technically not a “chlorine-free pool,” it’s just that the chlorine in the pool is simply not imparted from external sources like chemical pucks. The self-contained aspect of these systems is part of the draw. Because the system’s chlorine is constantly recirculating, it makes for a sustainable and regenerating system that, aside from an initial application of chlorine and salt at the beginning of the season, needs monitoring but relatively few adjustments or interventions. Self-regenerating systems are not omniscient – they generate chlorine at a consistent rate regardless of how the pool is being used. A lone swimmer will have a different impact than an eighth-grade pool party, for example. It falls to the pool owners to monitor pH and test the water chemistry, to avoid unwelcome fluctuations in the dosage of chlorine. (Too little and you can get a petri dish; too much and you’re in the red-eye zone.) Interiors turned to some local experts to discover what was behind this rising trend, and what consumers need to know to make informed choices.
Barry Justus, Poolscape: The first time I saw them was in Australia in 1985, when I was a young lad backpacking through there. So they’ve been around a long time. They’ve been in Canada for maybe the last 15 years.
Mike Mancini, Fox Pools: I first noticed this taking hold in North America about 10, 12 years ago, and these days the market for saltwater pools is fantastic.
Bill Bell, Bud’s Pools & Spas: Saltwater pools have been growing in popularity in North America over the last 7-10 years, really picking up over the last four or five years, but they’ve been popular in Australia for a long time. We installed our first saltwater system around 15 to 20 years ago.
Justus: It seems to be ease of use and cost-efficiency that’s driving interest. Chlorine generators are more costly initially, but down the road you’re going to save some money. I think people choose it for the convenience, mainly. It feels really nice on your skin and there’s less chlorine in the pool. It’s not perfect, but my clients like it. We use it in water features and hot tubs as well. Everybody wants it, pretty much. It’s very, very popular. It works well, it’s easy to use from a consumer standpoint.
Bell: Ease of maintenance in regard to pool operation is a big driver. You’re actually producing pure chlorine in the pool, but you’re also softening the water because of the salt, which comes in around 3,000 to 5,000 parts per million.
Bell: The number one concern is always the environment. The Toronto area has come out with a backwash bylaw that addresses problems with people discharging saltwater into the sewers. We’ve been selling these systems with cartridge filters – and you don’t backwash your cartridge filter, so your environmental worries are at a minimum. The bigger concern, I think, is often with road salt, which is a harsher form with more impurities than you’d use in a pool, and it’s applied more liberally. The other misgiving is, as I’ve said, the potential for corrosion. But generally if the customer is any good at looking after their pool – they don’t have to be diligent, just good with testing the water. And now they’ve come up with sacrificial anodes, which can be attached to your ladder, in line with the pump and filtration system, in your skimmer. Anodes are lengths of a softer metal, usually magnesium or zinc, that will draw corrosion to it. In other words, it will sacrifice itself before the ladder.
Mancini: Yes. The name “saltwater” should probably be “saline.” It’s not a misnomer, but it can be misleading. You’re looking at 3,200-3,300 parts per million, but in the ocean you’re looking at 45,000 parts per million. I’ve had some people tell me that they can taste the salt, but it’s purely psychological. It’s far gentler on the skin and eyes. The human body they say is 7,500 parts per million salt, and when you get into a pool with 3,500 parts per million salt, you’re in greater equilibrium with the water than you would be in a traditional chlorine pool. And it doesn’t allow your skin to dry out.
Justus: Our projects are really unusual. We charge for design, and that can get quite involved. Typically we do everything in 3D and it can take a month from the first time we meet a client until they get something that’s really hammered out. You’ve gotta go back and forth quite a few times in consultation with the client, either through e-mail or site visits. Often we’re doing something that’s a little bit off the wall, and we have to present our ideas to the client, make sure they’re in tune with it.
We recently did a fantastic project for Lino Losani, President of Losani Homes. We met him in August 2008, did ten different designs for him based around his thumbnail sketch – “I want a water feature, no pool, no maintenance” – and we went from there. By the time we finally finished the design work it was the spring of 2009. It took a while. And then we started work in April. How fast can it be done? We can turn around a 3D design for a client in a week, if things really click. And because our company deals with a smaller client base than most – we do three or four projects a year – we can spend more time with them, meet with them extensively. The project we’re working on right now is a spectacular indoor pool, and we sent then 27 design revisions yesterday. Minor stuff, but it’s all done in 3D, and the beauty of that technology is obviously that we can show the client what the end result will look like now, before we pour the concrete. It saves a lot of jack-hammering.
Mancini: You’re going to go anywhere from $1,500 on the low end to around $2,500 on the high end, and that just depends on the sophistication of the generator unit. You’re paying for your chemicals up-front, so you’re not having that $250-$400 cost per season. The second thing is hazardous material handling – liquid chlorine or chlorine pucks. You don’t have that anymore. Instead, you have the chlorine being generated right there in the system itself. And then also maintenance-wise, that’s my biggest beef: They work too well. The long-term costs end up being roughly equal. But the fluctuations of your pHs and your alkalinities are not as great. You’re looking at the same liner and construction as a typical pool. Our company takes the galvanized steel used in these builds and powder-coats it, and the powder coating exceeds the automotive perforation rating for salt, but we’re the only ones who do that. But as far as your lights, your pumps, your filters, everything like that is exactly the same.
Justus: You’re definitely going to cut down on your chemical use. There is concern that too much saltwater has been getting into the sewer systems when people go and drain their pools in the fall.
Mancini: The devices used in these pools are salt-chlorine generators. So they do manufacture chlorine, just a gentler form of chlorine. The process involves rejigging the salt molecule, and then you have the salt in the water, which helps soften it quite a bit. I like the system personally. It’s proven to be quite popular in North America, Europe, Australia, you name it. But some people are against the trend because when you backwash the swimming pool, you’re discharging salt into the environment. But you can avoid that by having a cartridge filter. And the second thing is the corrosion. They’re finding that saltwater systems can cause a bit of corrosion – what’s happening is that the systems work so well that the customers aren’t looking after the system the way that they should. It goes back to the chlorine in the water; it is capable of causing some corrosion.
Bell: All municipalities are looking to limit chlorine, algaecides, phosphates and the like – everything we put into the sewers has an effect on our water table. We’re becoming more involved with companies who produce progressive products such as enzyme-based and biodegradable products. But bylaws are likely coming into effect that will dictate what you can and can’t backwash. Saltwater pools may need to backwash into a sanitary sewer rather than a storm sewer. And of course you need to make sure the pool is bonded correctly. The initial, up-front cost is a lot more, but the biggest problem is the phenomenon of consumers who are being sold a system without the knowledge to operate it properly. There’s also the popular misconception that there’s no chlorine in saltwater pools; that’s false. There’s the misconception that there’s absolutely no maintenance needed. That’s also false. But they’re great systems, and if used properly and maintained properly, a saltwater pool is going to end up giving homeowners a lot of enjoyment.
BRIGHT IDEA: UV
Whether you choose to go with a traditionally chlorinated pool set-up or a saltwater one, you may want to consider installing a ultraviolet filter to lower chlorine requirements and make your pool safer. UV systems such as those made by SpectraLight claim to lower the amount of chlorine needed by up to 90 percent, destroy over 60 waterborne pathogens without using chemicals and eliminate dangerous chloramines and chlorine by-products. Recommended by the World Health Organization for swimming pool sanitation, UV systems reportedly result in pools that are healthier even though they’reless chlorinated. UV units destroy chloramines with a powerful, precision-engineered ultraviolet ray. That energy is a continuous, reliable, proactive method of eliminating high chlorine levels, and chlorine byproducts, but also nasty chlorine-resistant pathogens like Cryptosporidium, Legionella and Giardia, never the best pool pals. SpectraLight reportedly destroys bacteria, algae, viruses, cysts, protozoa and disease-causing pathogens such as E.coli with 99.9 percent effectiveness, and quickly – within two seconds after passing through the unit chamber. As they say, sunlight is often the best disinfectant.