By Marcelle Dibrell
A lot of pool service professionals say they have no use for specialty chemicals. A pool or spa needs nothing more than sanitation and balance, they say.
Strictly speaking, they are probably correct, but with so many specialty chemicals on the market that can truly improve the water’s appearance, why not invest in the little extras that can also make pool care that much easier? Many specialty chemicals are formulated for aesthetic purposes. Water clarity is a big deal for most pool owners and a large part of the reason they have hired a pool service professional in the first place.
Specialty chemicals like enzymes — designed to break down organic contaminants like lotions and oils — can provide a dramatic improvement in water clarity. For fine particulates that continue to escape filtration, flocculants and clarifiers are a nobrainer. And for a little extra sparkle, you can try borates, which a lot of users say gives the pool greater clarity yet.
Meanwhile, a pool that has become stained while under the care of a service technician is also unacceptable to most pool owners, who are perfectly capable of staining their own pools, thank you very much. That’s where sequestering agents and stain removers formulated by reputable stain specialists can really save the day.
And although algae doesn’t on its own pose any true health risk, it is certainly cause for alarm to most pool owners who are paying for professional maintenance. For one thing, it’s unsightly. For another, it’s gross. Third, it’s indicative of inadequate sanitation, which could mean bacteria and other diseasecausing pathogens are present. Fourth, it can stain surfaces. Fifth, it’s slippery and can lead to falls. Finally, it poses a safety hazard in terms of poor visibility and drowning risks. For all these reasons, the pool industry abounds with specialty chemicals designed to stop algae in its tracks, from a plethora of algicides that kill existing algae and prevent it from blooming in the first place; to phosphate removers that starve algae of a necessary food source.
Then, there are some specialty chemicals that go well beyond aesthetics, such as biofilm removers. There are a number of waterborne pathogens that can cause moderate to severe illnesses and thrive in the warm environment that hot tubs and spas provide. Many of these pathogens live in the biofilms that tend to coat the internal plumbing. The biofilms are highly resistant to normal disinfection and tend to form when sanitizing efforts are sporadic. In a hot tub, biofilms are a rich mixture of bacteria, fungi, algae, yeasts, protozoa, and microorganisms combined with hair, skin cells, and debris that attach to the hidden inner walls of pipes and plumbing components.
The dead skin cells and batherintroduced bacteria quickly deplete sanitizer levels. If this depletion is left unchecked, the bacteria and debris will eventually begin adhering to the internal plumbing, forming biofilms.
These biofilms provide a perfect breeding ground for the troublesome pseudomonas bacteria, the potentially deadly legionella bacteria, and more. So beyond aesthetics, an EPAregistered biofilm remover is a must for a hot tub and spa service professional.
This special issue of Service Industry News is all about specialty chemicals: How they work; what they do; and how to use them.
Biofilm Removers
Every year, dozens of Americans become sick and some die after contracting Legionnaires’ Disease in a spa or hot tub.
This spring, five guests contracted the disease at the Clarion Pointe Wake Forest Hotel in Winston-Salem, North Carolina. The culprit was the spa.
In the summer, a couple visiting a Marriot hotel in San Jose became sick with Legionnaires’ Disease. The hotel’s spa tested positive for Legionella.
Beginning in 2021 and continuing through May of this year, five guests contracted Legionnaires’ at The Grand Islander by Hilton Grand Vacations in Waikiki, Hawaii. The investigation of the source is still ongoing.
Between the Fall of 2021 and early 2022, health officials confirmed 20 cases and two deaths from Legionnaires’ in Riverside County, California. Eight public pools and spas were closed as authorities attempted to identify the source.
According to the CDC, Legionnaires’Disease is a serious type of pneumonia caused by Legionella bacteria. About 1 in 10 people who get Legionnaires’ Disease die from it. Nearly 15% of Legionnaires’ Disease patients reported staying overnight at hotels, private homes, or vacation rental properties.
About half of Legionnaires’ Disease patients who reported travel and staying at a vacation rental property also reported using a hot tub.
Outbreaks such as these occur even in water that appears clean and cared for, largely because of biofilm in the plumbing.
When microorganisms such as bacteria, fungi, and algae gather together on a surface and then coat themselves with slimy substances, they have formed biofilm. Biofilms can start with just a couple cells and then grow into huge colonies that contain a wide variety of organisms.
Many bacterial pathogens such as Legionella like to live in biofilms and will often thrive and reproduce quickly in a biofilm environment. Once a biofilm becomes established on a surface, it can be very difficult to treat. Although swimming pool and spa sanitizers are very good at killing microorganisms that are free floating in the water, it is difficult for them to get down through the slime layers of biofilm and kill all potentially harmful organisms. If only the top layer of organisms is killed, the cells underneath can continue to grow and reproduce, thereby reforming the biofilm structure in a short time.
That is why it is possible for a spa with adequate chlorination levels to continue to host biofilms and their associated microorganisms.
There are a number of spa purges and jet cleaners that are readily available for the pool and spa industry. Many formulations contain enzymes, which have been demonstrated to break down the organic components that are part of the biofilm matrix such as human skin cells, hair, oils, makeup, sunscreens, dead algae, and more.
To make a biocidal claim, however, the Environmental Protection Agency requires the product to meet specific testing criteria. Furthermore, they discriminate between the different types of claims that can be made. For example, a product may claim to remove biofilm without actually killing it. A product may claim to prevent biofilm. A product may claim to control or reduce biofilm. Finally, a product may claim to kill biofilm. There are different testing guidelines for each of these claims.
To the best of our knowledge, there is only one company that manufactures an EPA-registered biofilm removal product. They make the only products in the spa industry that can claim to remove biofilm according to the EPA.
Manufactured by Unique Solutions, the products are called Hot tub Serum, composed of Alkyl dimethyl benzyl ammonium chloride, and Ahh-some, composed of Alkyl dimethyl ethylbenzyl ammonium chloride. These products are EPAregistered as effective against both algae and animal pathogenic bacteria (gram positive and negative.)
Hot Tub Serum Hot Tub Serum is the only laboratory-formulated blend of water cleaning agents and salts shown to kill both E-coli and Legionella in hot tub plumbing, even as it balances hot tub water. This minimizes the need to test and adjust individual water characteristics and chemicals in the spa. Hot Tub Serum utilizes a specific combination, which acts to treat the spa and the plumbing, protecting the hot tub and extending life to hot tub components like heaters, jets, and pumps.
1. How do I use Hot Tub Serum? Add half a jar of Hot Tub Serum Total Cleanse per 400 gallons to hot tub water to purge and clean the plumbing lines, and run jets for 20 minutes before draining. Clean spa surfaces and remove and rinse filters. Refill hot tub with clean water, reinstall filter, balance, and add sanitizer. Add 1 oz. Hot Tub Serum Total Maintenance per 100 gallons water every 7 days. See www. serumwatercare.com for full usage instructions.
2. How does Hot Tub Serum work? Cause vs. Effect Hot Tub Serum works by reducing the surface tension of the water, making it very difficult for bacteria to attach to a substrate and form the protective biofilm. Hot Tub Serum destroys the bacteria that forms biofilm. Chlorine and bromine are two sanitizers that are ineffective against these types of bacteria. The result when you use Hot Tub Serum in a spa or hot tub is clear, fresh smelling water with a soft, silky, nonirritating feel and little or no bacterial content.
3. Will Hot Tub Serum sanitize the water in a hot tub or spa?
No, however it does contain mitigating agents that help keep water clean and minimize bacterial growth. The effect: Hot Tub Serum eliminates the opportunity for bacteria to get a foothold in the first place and breaks the cycle of bacteria buildup, thus minimizing risk of foul water.
4. So, I still need to use a sanitizer in a hot tub or spa, right?
Yes, as instructions indicate, the regular use of a shock after bathing eliminates the body wastes being left in the water like sweat, skin, hair, body lotions, dust, etc. that act as food for bacteria. Hot Tub Serum does not eliminate these. If you do not have ozone or also use a mineral ion cartridge, it is recommended that you use a weekly dose of enhanced shock granules as an additional safety measure.
5. Will Hot tub Serum help a spa in any other way?
Yes, the weekly use of Hot Tub Serum Liquid will also eliminate bacteria from the underside of the cover by the condensation created in the spa. By eliminating the growth of bacteria on the underside of the cover the brown or black spotting will disappear and the cover will not have a foul odor, keeping it clean and fresh. No other sanitizer or enzyme product has any effect on the cover.
6. What is the difference between Hot Tub Serum and an enzyme product?
By adding enzymes to spa water, you are attacking the biofilm and bacteria that already exist in the spa. But enzymes are a band-aid trying to cure a problem that already exists. Hot tub Serum eliminates the problem in the first place, so there is no biofilm forming in the spa.
7. What are the benefits of Hot Tub Serum?
The biggest benefit of Hot Tub Serum in a spa is the inability of bacteria to gain control of the spa. It also eliminates on average of 15 minutes a week that you usually spend measuring, adding, and testing various products. The peace of mind from knowing the hot tub water is always perfectly balanced is enormous. Another major benefit is the elimination of foul smells and odors in the water and the resulting residual smell left on the skin. Last, the good bacteria on the skin are not affected by Hot Tub Serum. The natural oils are maintained, and there is no dry, itchy feeling after leaving the spa. It’s proven safe for those who suffer from psoriasis. This benefit alone has enabled thousands of hot tub owners to use their spas again.
8. Is Hot Tub Serum safe? Hot Tub Serum meets all U.S. and international standards for safety and reliability when used as directed.
9. Does the product have a guarantee?
If the product doesn’t work to keep your customers’ water clean, clear, and smelling good, and if their skin doesn’t feel soft and smooth without itching or flaking after using their hot tub, they can return it for a full refund.
10. Is the product EPA registered? Hot Tub Serum Total Maintenance has been granted EPA registration (EPA Reg # 84409-2). EPA registration is significant in that the U.S. government has reviewed the science behind this biocidal formulation and has concurred that it is effective for its intended purpose and poses no significant risk to humans or the environment when used and handled as specified on the label.
Enzymes
There are plenty of pool industry experts who will tell you that beyond water balancing chemicals, there is no need to add any chemical other than chlorine to keep pools clean. But with so many specialty chemicals out on the market, should we rely on chlorine alone to handle organic matter?
It is important to remember that there must always be a residual of free available chlorine in recreational water for sanitation or disinfection. And if chlorine is used up oxidizing organic waste, its ability to sanitize can be affected. Chlorine is an excellent sanitizer and disinfectant. But the majority of contaminants that chlorine attacks are non-living organics.
Imagine you know a genius doctor capable of developing a cure for cancer, but instead of employing him in the field he excels in best, you give him a job as a dishwasher. It’s a waste of good talent.
It’s kind of like that with chlorine. We would be better off allowing chlorine to do what it does best, which is disinfection. So, by incorporating secondary systems such as ozone, UV, and advanced oxidation processes (AOP) to handle the oxidation component, we can free up chlorine to work on the sanitation part.
Enzymes can also do this. Using NSF-50 Certified enzymes as directed by the manufacturer can to help handle non-living organic contamination. NSF-50 is the recreational water safety standard for equipment and chemicals. The NSF tests products with intense scrutiny to see if the products meet the standard. The registered trademark NSF mark is then put on the label of such products that meet the standard.
Chlorine gets used up quickly oxidizing bather waste, but wellformulated enzymes handle bather waste without trouble. It is important to understand that enzymes are not sanitizers, so they aren’t effective against living organisms. They only work against carbon-based organic waste, such as body oils, sweat, lotions, sunscreen, tanning oils, cosmetics, hair products, deodorants, and pet dander.
These non- living organic contaminants are the bulk of what chlorine has to work against in a pool without enzymes. Why not let enzymes do the heavy lifting? Worldclass water clarity could be the result.
Phosphate Removers
Has anyone ever gotten revenge on a person by dumping a bag of fertilizer in their pool? In theory, at least, a little Miracle-Gro could cause a nightmare of mysterious algae problems.
That’s because phosphates are an essential nutrient for algae growth, among other food sources.
According to the IPSSA Intermediate Training Manual, “Nutrients are present in several forms in pools and spas including dissolved inorganic, dissolved organic, particulate organic, and biotic forms. Only dissolved forms are directly available for algal growth: for nitrogen and phosphorus these include Ammonia (NH4), Nitrate (NO3-), Nitrite (NO2-), Orthophosphate (PO4-3), as well as dissolved Carbon Dioxide (CO2) and dissolved Silica (SiO2).”
Ultimately, high phosphate concentrations in a pool can result in increased chlorine demand, and at exceptionally high levels, render chlorine ineffective in the battle against algae. It’s not that chlorine reacts with phosphates — it doesn’t. Rather, in the race between the killing rate of chlorine and the reproduction rate of algae, phosphates behave like performance-enhancing drugs for the algae, leveling the playing field.
As pool chemistry expert Richard Falk puts it, “The rate of chlorine kill is the same [with high phosphates], but the rate of growth [of algae] can be slower with low phosphates. It’s a race of reproductive growth that is faster with more phosphates (up to a limit determined by sunlight and temperature) vs. killing by chlorine.”
The algae is simply growing faster than the chlorine can kill it.
That’s why NSF-50 certified phosphate removers can be an effective tool in a service professional’s arsenal of weapons against algae. Phosphates above about 500 ppb can create mysterious algae problems.
It’s important to realize that phosphate removers do not actually kill algae. Chlorine or alternative sanitizers do the killing. Furthermore, any chemical that makes killing claims is required to be registered with the EPA. That is why it is not necessary or even possible for phosphate removers to obtain EPA registration.
The NSF-50 certification, on the other hand, is the stamp of approval by a group of manufacturers and industry experts who have verified that a product actually does what it claims to do. If a manufacturer has obtained NSF-50 certification and later alters ingredients or changes the product’s concentration such that the product no longer performs as well, the manufacturer can incur penalties and lose its NSF-50 certification.
Borates
Popular use of borates is increasing due to user’s assertions that it can lower chlorine demand, help prevent algae, stabilize pH, increase the service life of pool equipment, and improve the look and feel of the water. Borates are also useful with salt-water-chlorine-generated pools to keep the pH from rising. Those are a lot of bold claims. While chlorine is selling at a premium, now may be a good time to try them and see if they live up to all the hype.
How to use Borates The optimal concentration of borates in a swimming pool is 50 ppm. This is calculated as parts per million boron. Getting to that concentration of borates will depend on the type of borates you are starting with. It can be added as boric acid, as borax, as a neutralized borate, and as sodium tetraborate pentahydrate. In general, adding borates can be expensive. However, it is only really necessary to add borates once, unless the pool is drained, because borates don’t degrade or get used up.
Boric acid
Boric acid, which is available as a pesticide, is available in small quantities from hardware stores, but larger amounts can be found online. Adding boric acid to the pool is relatively cheap and easy, and it does not usually require a pH adjustment following treatment, which further lowers the cost.
The rule of thumb is that 4.75 pounds of boric acid will bring 10,000 gallons of water to 10 ppm.
Borax
Borax, or sodium tetraborate decahydrate, is readily available in most grocery stores under the trade name 20 Mule Team Borax. During application, it is necessary to neutralize the pH rise that will occur upon addition of borax.
It takes 9.5 pounds of borax to bring 10,000 gallons to 10 ppm and requires 76.8 fluid oz. of acid to neutralize the resulting pH rise.
To Dose: 1. Adjust the total alkalinity to between 70 and 80 ppm for salt pools or pools using hypochloritebased chlorine. For Trichlor, adjust alkalinity to about 100 ppm.
2. Adjust pH to between 7.4 and 7.6.
3. With the pump running, add half of the calculated acid to the pool. Pour it slowly at the returns or dilute about 1/2 gallon at a time in a 5-gallon bucket of pool water and broadcast it around the pool.
As soon as the acid is in, add half the borax.
4. Brush down the sides of the pool all the way around. The goal is to thoroughly mix the solution.
5. When brushing is complete, add the rest of the acid and the rest of the borax and brush again.
6. Allow the pump to run for 24 to 48 hours.
7. After 48 hours, test the borates and pH. It may be necessary to add more acid to bring the pH down.
8. Test the borate levels monthly. If the filter is frequently backwashed, it may be necessary to test a bit more often. When the borates drop to about 30 ppm, increase them another 20 ppm to bring them back up to 50 ppm by adding the acid and borax. Sodium Tetraborate Pentahydrate
Sodium tetraborate pentahydrate is added to the water in a manner similar to that of borax. However, because it has half as much water as the decahydrate form, less will be required.
It requires 5.6 pounds of sodium tetraborate pentahydrate to bring 10,000 gallons of water to 10 ppm, and 10 oz. of muriatic acid to neutralize every 1 pound of sodium tetraborate pentahydrate.
Neutralized borates
It is possible to purchase borate products that contain pH neutralizing chemicals such that it is not necessary to add muriatic acid after treatment. The directions say to use 2 pounds per 1,000 gallons.
Algicides
When it comes to most specialty chemicals, the Environmental Protection Agency doesn’t exert much control. But the story is entirely different with algicides, which must be registered and approved as such. Algicides must undergo thorough testing procedures that ensure the chemical’s safety and efficacy.
Algicides and algistats come in several forms.
The most common include quaternary ammonium compounds and polymeric quats.
Quaternary ammonium compounds, or “quats,” are positively charged nitrogen-based compounds. Because the cell membrane of algae has a negative charge, electrostatic forces attract the nitrogen of the quat to the algae’s surface. Many quat molecules are attracted to the algae cell and surround it, working by disrupting the algae’s cell membrane. That positive charge also attracts dirt, working like a clarifier to send it to the filter. Quats are a preventative step against algae.
The molecule is similar to a surfactant and like soap, can get sudsy. That is why quats are not suitable in spas.
Polymeric quats, or “polyquats,” are similar to quaternary ammonium compounds, but they are a much longer molecule, made of repeating carbon-based groups. They were designed to reduce the foaming issue that quats have. Because they are larger molecules than quats, they work a little slower. Polyquats are another preventative step against algae.
Copper-based formulations are also effective against many kinds of algae.
Some of the registered copper algicides include copper sulfate and copper ethanolamine, or triethanolamine. Chelated copper helps prevent staining surfaces, which tends to happen with copper salts like copper sulfate. Copper-based products disrupt cell division and kill algae by causing fluid leakage from cell membranes.
Copper algicides are very effective on green and mustard types of algae. They tend to work best at elevated pH’s from 8 to 8.4 The major disadvantage of using copper products is that they can cause staining over time, especially when chlorine or other oxidizers break down the chelating agent.
When adding any chemical, it important to carefully follow the directions. Copper-based algicides will stain surfaces if the copper concentrations get too high — even if the copper algicide contains chelators or sequestrants.
After a few months, the chelator can break down, allowing the copper to precipitate out. The first sign of this is blue or green water — often misidentified as an emerging algae bloom. If there is no appreciable change in chlorine demand, it is likely to be copper.
Silver-based algicides are also effective against algae. They work by interfering with metabolic activities. This algicide comes in the form of
