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Saturday, January 28, 2012


Better Control, Less Work, Less Worries

     With new advances in technology and research available in our industry, we are now able to automate our pool controls and ensure better water quality.  Automation of controls minimizes operator error and can adjust water chemistry to maximize our sanitation control.  This is especially helpful in a managed aquatic facility or large pool setting.

     Sanitation of the pool water is the most important task for a pool operator.  A trained pool operator also knows that just adding chlorine is not enough to accomplish the job of disinfection.  The operator must know what the demand on the sanitation is according to bather load, temperature, pH, and many environmental and chemical factors.  Up to now the operator used breakpoint chlorination calculations and a fair amount of guesswork based on the gallons and flow rate of the pool.  With the introduction of ORP control units (Oxidation -Reduction Potential) we are now able to measure with sensors the quality of the pool water.  Quality of pool water is a measurement to oxidize contaminants.  This is measured in millivolts which is the count of the electrical charge available by the chemical molecules. When you oxidize (oxidation) microbes and organic material you reduce (reduction) the contaminants in the water.   The level of measurement is the potential the water has to be able to oxidize and reduce contamination.

     If we are constantly monitoring and adjusting the potential of the water then we are using dependable and accurate analysis and adjustments so that a build-up of contaminants such as chloramines does not occur.  The reduction of chloramines prevents swimmer discomfort and creates a pleasant swimming environment.  It also allows continuous control of bacteria, virus and parasites that can contribute to Recreational Water Illness. 

     As the effectiveness of sanitizer is dependent on pH then it is helpful to have a pH sensor in the ORP system.  As the pH rises then there is less oxygen associated with the sanitizer available to work.  The opposite would be that if the pH was low then there would be more oxidation.  However, this is not a measurement of sanitizer level and we need to establish a protocol of adjusting the pH first before adjusting the sanitizer. Automatic adjustment of pH by using a sensor and dispensing unit that is working simultaneously with the ORP system establishes the protocol of pH adjustment first then addition of oxidizer second if needed.

      We are only using the amount of sanitizer and acid needed to maintain a properly sanitized pool with ORP and pH automation.  There is no over dosing or under dosing of the pool chemicals by the operator, which can increase operating budgets.  Also, the pool operator does not have to manually make adjustments as often.  This allows a shorter exposure time to handling dangerous chemicals by the operator.

     We can be assured of quality control that is dependable and accurate, resulting in better sanitation that requires less work on the part of the pool operator.

Thursday, January 26, 2012

Why Use Ozone in Spas and Hot Tubs?

Simply put, Ozone is a natural oxidizer of wastes in water that could be harmful or cause unpleasant smells and cloudy water. The makeup of ozone is 3 Oxygen molecules that have a strong potential to change micro organisms such as germs and virus, into a state that is not harmful to bathers otherwise known as oxidation.

Air is drawn by one of two different types of ozonators (corona discharge or UV light) and becomes ozone. This is a process that duplicates the ozone being manufactured in our upper atmosphere by the sun. However we are controlling the process of ozone manufacture in our vessel. Without control of the ozone process there can be negative effects associated with too much ozone gas which is not healthy. However being controlled in process for our water and not combined with diesel fuel by products there is no comparison of danger as in air quaility issues.   Many times ozone for water quality management can get a bad reputation by being confused with the non controlled manufacture of ozone. As in any environment with humidity there should be adequate ventilation to prohibit water borne bacteria from being inhaled and in turn this ventilation will prohibit any exposure to a buildup of ozone gas as well.  Properly sizing the unit so that it does not over produce or under produce is also of importance when installing.

Ozone does not leave a residual in the water so it is used as a secondary oxidizer. It is recommended to use ozone in conjunction with chlorine or bromine (only in residential spas) so there is a continuous sanitizer level to prevent micro organism growth (disinfections). But it does not leave chloramines, bleach bathing suits, or damage the equipment. When ozone is used up it reverts back to oxygen which is natural as the air we breathe.

Other benefits to ozone are that you can reduce your chemical usage and there are not strong unpleasant odors to it. Because it helps keep the water cleaner you may be able to go longer between water changes as well.

Ozone is 3,000 times quicker than chlorine in killing micro organisms but yet is relatively safe. It is especially useful in killing Cryptosporidium, Giardia, Legionella and E Coli which account for the increase in RWI’s (Recreational Water Illness’s) our industry is seeing. It is not expensive and only needs to be replaced depending on the hour life. This may be 1 – 2 years but depends on the unit. If you have not had your hot tub checked recently to see if the ozonator is operational it is well worth the money for your safety to have this done by a professional.

With hot water bacteria breed quickly and the small amount of water per person ratio that is in the hot tub make it necessary to take extra precautions to maintain a safe, healthy environment for your enjoyment.

Tuesday, January 24, 2012


K.I.S.S. - Keep It Salt for Safety

You might think that manufacturing your own chlorine at home would be dangerous and unwise. You might think that adding chemicals to your pool is also dangerous and unhealthy. Both of those statements are false.

The manufacture of liquid bleach (chlorine) by using salt and a small current of electricity was started in the 1800’s. Now we can do this safely right at and in our pools and spas.

As chlorine works by oxidation which is the ability for a molecule to grab and burn oxygen we must use chemicals that promote this reaction to rid our pool/spa water of waste and bacteria. This would require the oxidizer used to be unstable so it can react quickly. We see this in fire situations where we are told not to open a door where there is a fire. Increased oxygen flow increases the ability to burn and flame. An oxidizer has the ability to burn, combust and explode depending on how fast it reacts with another chemical or product. This makes storage of oxidizers or shock products such as calcium hypochlorite and sodium hypochlorite dangerous to store in your home or business. You may be required to post a warning or informational card on your home, business or vehicle when transporting. We know that adding water TO calcium hypochlorite can cause an explosion. If a fireman comes to your home and business and sees a pool in the backyard they are wondering where you store your chemicals for they do not want to put a stream of water on a container of this strong oxidizer and create a worse situation.

The storage and handling of chlorine is also a problem that could be costly and dangerous. The fumes are very corrosive and if product is stored near lawnmowers, chain saws, chemical controllers, pumps and other usually stored items damage will occur in a short period of time. Unopened containers of chlorine can become brittle and crack allowing product to come in contact with grease or oils and ignite. Fumes are also dangerous to breathe and precautions for breathing and eyes must be taken when opening and dispensing.


Chlorine generators have no storage of dangerous products. The main product used is salt and there is no need to store any. Even if you did store salt it is not dangerous. It’s not expensive either.

With manufacturing the chlorine yourself the costs come down dramatically for sanitizer. The salt only needs to be replenished when the chloride (salt) level gets low due to splash out, leaks, backwash or dilution of the pool water. The salt stays in the pool during evaporation but can leave on swimmers and any way the water is physically removed. With rising costs of inorganic chlorine salt generation is economical and all of the initial costs can be recouped in a short period of time.

A disadvantage would be the initial cost of the unit and installation. The initial costs are much higher than an erosion feeder and it seems odd to be adding hundreds of pounds of heavy salt bags to your pool initially.

What is convenient is that to super oxidize the pool as needed you can just turn the production up on the unit or use a non-chlorine (MPS) type shock. There is no mixing of chemicals, fumes or work involved other than testing the water regularly to keep pH in correct levels.

It is still a chlorine pool so our water chemistry practice is still the same. Keep the chlorine level at 1.5 ppm to 3ppm and balance the water within parameters. However we do keep the total alkalinity at 80 ppm to 100 ppm to help us keep the pH at an acceptable level.

The mineral salts make the water feel soft and luxurious. It has the “ahhh” effect on people. Saline solutions are used for contacts so you know that the salt in the pool will not burn your eyes or delicate parts.

The pool does not taste like salt as it is not over 30,000 ppm such as seawater. But it does not have a steel taste either that can be found in pools with low pH and alkalinity levels. Pool water likes to be balanced and go to a pH of 8. However a pH of 8 is not acceptable in a chlorine pool as the weak chlorine (OCL) becomes more bountiful. Therefore we need to be sure as we do in all chlorine pools to keep the pH in range of 7.4 - 7.6.

Due to the electron process the cells can scale up so there is a need to acid wash the cell periodically.

As the pool is higher in total dissolved solids from the minerals of the salt it is more conductive to electron flow. This can cause some corrosion in a pool that is not properly bonded. However a inexpensive zinc anode can be placed in the skimmer basket to help counteract the process.

With producing chlorine on site the pool water keeps a steady residual as it is not depending on a feeder (human or automated). With less chances for a low sanitizer event then it is less likely that algae, biofilm or bacteria are allowed to grow. Evidence is suggesting that many oxidants can be formed within the water and further decrease biofilms. It is imperative to keep chemicals in the pool to combat bacteria, biofilm and other pathogens as they are more dangerous than the recommended chemicals.

There are three available models of chlorine generators: brine, in-line, and in-pool. I prefer the in-line model due to it’s convenience and available options. The in-line model is comprised of a cell with housing cord and power supply. Some models have a temperature probe that can increase and decrease the chlorine production automatically. Some models will read the actual salt reading in the pool where as some read an average of the past 30 days. It is important to know which type you have to avoid problems. Some in-line models will stop producing chlorine when the salt level is too high or the water temperature is above 96 degrees. This disadvantage does not have to be as long as you know what to expect.

The in-pool units can be a nuisance as kids may want to play with them. Brine tanks have to be monitored carefully as the by product of caustic soda has to either be drained or introduced into the pool.

As with all equipment there can be a failure and a resulting down time. It would be recommended to keep a back up method of sanitation for times as this.

Salt systems are not new to the pool industry. However they are more user friendly than ever before. You do not need to be a chemist but you need to have a good pool professional to check your water periodically or have a good understanding of water balance and recommendations for salt water pools.

Less work is a nice by product of the safety issues that present themselves when using a chlorine generated pool. The safer the pool and safer the water provides a safer environment bathers and community.

Sunday, January 15, 2012

Biofilm: The Hidden Accomplice

Biofilm: The Hidden Accomplice

So many times when I hear the word biofilm all I can conjure is the movie BioDome and how much the two are alike. They are two protective enclosures with living organisms that can contain within themselves one or many different types of living organisms. But they are also different in that BioDome was many organisms working for a common good and being self sufficient where as biofilm is a nuisance due to its ability to harbor bacteria, fungi, algae and protozoa. Of course the movie did portray Pauley Shore to be a nuisance and example of what can go wrong. The same is true of the hidden accomplice of biofilm.

Biofilm is formed by the combination of water, a surface to grow on, and microorganisms. The water needed can be as little as high humidity and can be fresh or salt water. Surfaces can be solid where most types grow but also biofilm can grow on biological surfaces like organs. Microorganisms such as algae, bacteria, protozoan, fungi or a combination of such can be present in biofilm. Some are harmful that can cause illness such as Legionnaires disease, Pseudomonas rash, and intestinal illness as with giardia, e-coli, and cryptosporidium.

In our swimming pool environment we encounter water everywhere. The outside environment including the deck, chair and bench surfaces to of course inside surfaces of the pool including the piping. The moist outside areas out of the pool can harbor microorganisms that can be transferred into the pool.

Biofilm that is attached to a surface is more resistant to disinfection. In the pool there are areas of poor circulation or dead zones that will allow the microbes to attach themselves to the surface easily. In pools where the circulation is stopped such as in use of a timer, biofilm can began to grow easily. This is not an area that can be brushed. In circulation piping if the velocity of the water is fast the biofilm experiences erosion and it becomes smooth creating a strong biofilm harder for chemicals to penetrate. If the velocity is slow the biofilm will be rough and have an uneven surface creating an unstable biofilm. [Klueger and Meyer] Biofilm that has broken off and is free floating is more susceptible to disinfection.

Microbes are smart. They can talk to each other through chemical signals and know when to colonize. Once the microbes attach and start to colonize they secrete an Extracellular Polymeric Substance otherwise known as EPS or that slimy, sticky covering that protects the colony from normal levels of sanitizer and algaecides.

Then they invite their friends. So many different living organisms can be in the biofilm. They release part of the colony to find new areas to grow and find more friends. Also any harmful microbes can be released and cause a recreational water illness. The CDC has found that 65% of RWI (Recreational Water Illness)  involve a biofilm. [NSPF Pool & Spa Handbook, 2011 Edition]. The microbes can wait around in a well maintained pool or spa for an opportunity to get established again like when the sanitizer or algaecide level is low. Once treated for biofilm it is important to keep a higher than normal sanitizer level so they don’t come back again and again.


The conventional methods of microbe control for swimming pools have proven inadequate when associated with biofilm. Biofilm prevention is recommended as it is much harder to eliminate once allowed to establish.  However there is evidence of less to no occurence and ease of removal in salt water systems.  See Mixed Oxident Solution for further information and pictures.

Dental plaque is a type of biofilm. We brush our teeth to remove the biofilm and prevent dental decay, bad breath and such. The same is true in our pools and spas. If we perform regular brushing of all surfaces in the pool we can dislodge the biofilm that may be present so that it becomes free floating and more able to be disinfected by the sanitizer and algaecides we keep in our pools. Brushing the walls, skimmer throats, under ladder treads and around lights and fiberglass steps is a must to prevent biofilm from forming. As these can form on decks and be introduced into the pool it is wise to also periodically use bleach and scrub the deck area as well.

Keep an optimum level of sanitizer in the pool at all times not just when it is being used. This includes the off season of pool and spa use. If a spa is drained there are usually wet surfaces in the pipes that can form a biofilm. The majorities of spas are “wet tested” after manufacture and then may sit for long periods of time before having water introduced for use. This is why many spa manufacturers recommend that the spa is filled, super chlorinated, jets run and spa circulated for a few hours, drained and then refilled. I have found that when this is not done within a couple of weeks the water turns cloudy due to biofilm and cannot be cleared up with conventional methods.

If a pool is winterized the same can happen in the plumbing. Water mold although a different structure uses biofilm to adhere and during these dormant times is easily established. I have found that raising the chlorine to a minimum of 10ppm or more upon pool opening after a winterization has decreased the number of spring water mold and algae complaints. I use this method for chlorine and biguanide pools.

Cleaning of the filter is very important to discourage biofilm as well. If a filter is acid washed only but no degreaser type cleaning done the biofilm will not be removed. [Biofilm: That Gooey Stuff, Connie Sue Centrella]

Brushing of surfaces, keeping sanitizers in the recommended range at all times, weekly chlorine treatment of 10ppm, regular testing, chemical filter cleanings and the use of algaecides and enzymes are the best tools for combating biofilm.

Many pool and spa owners do not want to add more chemicals than necessary for fear of bad chemical implications. It is important to educate these owners that improper chemical levels and poor housekeeping is more of a hazard to their health.

Just like in the movie BioDome when it looked like all life had been destroyed one green leaf of vegetation started growing again. And in pools/spas you may think the biofilm is gone but one microbe that has survived can start the biofilm again.


Research materials used:

Understanding Biofilm in Recreational Water Environments, James J. Miller MS

Biofilm: That Gooey Stuff, Connie Sue Centrella

Understanding and Combating Biofilm, Todd Klueger & Ellen Meyer; Arch Chemicals
Miox Corporation: Biofilm Removal

Thursday, January 12, 2012

Don't Scrub Use Enzyme Technology

Work Less Use Enzymes
Work Less Use Enzymes
Enzymes are natural proteins made from a renewable fermented source that once introduced into a pool or spa, are able to collect and break down oils and other inorganic matter in the pool. Enzymes can be effected by temperature, water chemistry and environment. Due to this, it is important to use enzyme products specifically for pool and spa water. Enzymes can come in different strengths that can be used at different temperatures. As they are a protein they do have a shelf life and need to be stored in an area protected from freezing and high temperatures.

Enzymes break down the organic waste into carbon dioxide and water.

Suntan lotion, oils and organic matter float in the water, collect dirt and then deposit onto the walls and other surfaces such as the filter. The scum line or bath tub ring in a pool or spa is a visual occurrence of this. The enzyme will collect this oil and be lifted off the wall. A surfactant in the enzyme product or algaecide used in the pool will help in this process. A physical advantage of this would be the feel of "softer" water. Another advantage is that the scum line will be removed without laborious scrubbing and if enzymes are added on a regular basis another scum line will not form. This means less work which is always appreciated.

If you can see the scum line being removed just think of how well it works where you don't see, like the filter and plumbing. This cleaning action of the enzyme in the filter will keep the filters from having to be manually cleaned as much, and again less work. Also this allows the filters to work better for longer periods of time between needed backwash or manual cleaning, giving you a cleaner pool. Using enzymes help to prohibit biofilms from establishing and adhearing to the pool surfaces. Also, you will consume less chemicals as the enzymes destroy some of the inorganic matter that usually will consume sanitizer and algaecide. Enzymes also help to clear up a cloudy pool by destroying the waste that may be too small to be filtered.  Enzymes are not a clarifier and do not cause smaller particles to form larger particles for quicker filter removal. 
 

Wednesday, January 4, 2012

Basic Algae Fundamentals

Basic Algae Fundamentals

Algae are a type of plant life that blooms everywhere.  In swimming pools if given a chance, they are a nuisance that consume sanitizer, raise pH and give an uninviting appearance to swimmers.  They can stain swimming pool surfaces if not treated quickly and become more colonized and harder to remove.
We most often see green algae, black algae and mustard or yellow algae in swimming pools and spas.  I have often seen combinations of these in a pool that has had a lapse in chemical maintenance and/or housekeeping.  Algae can be introduced into the water by environmental factors of anything or anyone that enters the water, drops in the water, or blows over the water.  Infestation can be welcomed by improper by sanitation levels, improper pH, and lack of algaecides.  Phosphates and also nitrates that can be introduced into the pool help to feed the algae.  Nitrates can be introduced into the pool by a simple summer thunderstorm with lightening.  You may be unaware that a cleaner you have purchased for the pool may contain phosphates. 

The best way to combat algae is to use preventative steps.  Be sure you brush the pool often to prevent the algae from attaching to a wall.  Keep organic debris out of the pool by checking your skimmer and pump baskets often as well as cleaning leaves and dirt out of the pool.  Robotic cleaners are a great help in keeping the pool wall surfaces scrubbed and cleaned.  Regular testing of pool water and the addition of proper sanitizer, preventative algaecide and flocculent helps combat algae from blooming in the pool water once introduced.

However, if you do see algae it is best to treat immediately.  Test to see what your free available chlorine residual is.  If the level is low then a shock treatment may kill the algae bloom.  Remember to watch your pH and keep in the proper range so that the chlorine is effective.  However if this does not work a use of an algaecide may be needed.

Many forms of algae have a covering that helps to protect them.  Algaecides help to break open the covering so that the algae cells can be destroyed.  Quat type algaecides do this very well for green algae and are effective in all types’ pool sanitizers including biguanides (Baquacil).  They are not effective in penetrating the cell membrane of yellow or black algae.  However they can cause foaming if more is added than is needed to perform the job since they are also a surfactant. 

Surfactants make the water wetter and break up any air bubbles that may be between the pool walls and the treated water therefore allowing the treated water to come in direct contact with the wall.  This makes quat algaecides a wonderful preventative algaecide as well.

It is not recommended to use a quat type algaecide in a spa or in a pool with fountains or waterfalls as this can increase the foaming.   Polyquat type algaecides have been developed for use in pools with fountains or waterfalls as this type of algaecide does not foam.  Polyquat algaecides are very effective at penetrating the cell membrane and also coagulating the algae for easier filter removal.   Be sure to follow the label instructions for use on all products.

Sometimes algae are resistant to the above treatments such as in the case of yellow (mustard) and black algae.  These algae form a formidable shell around them and require a more diligent treatment.  Metal algaecides such as copper and silver are best used for this type of tough algae.  Care needs to be taken to follow the proper instructions.  An abundance of metals in the presence of chlorine can cause staining to occur.  Many metal algaecides are now chelated so that staining does not occur.  This is true if there are no other untreated metals in the pool water.  Always test to see if there are metals present before treating with a metal algaecide.  If not using a chelated metal algaecide be sure to use a sequestering agent after treatment to remove the excess metals and prevent staining.

But what if the algae just keeps coming back or you just can’t get the pool cleared again?  Algae can also be caused by a lack of sanitizer due to a biofilm being present in the water such as water mold or pink slime.  Biofilms are organisms that are held together with a gooey substance that adhere to wet surfaces or are in wet environments and free floating.  Dental plaque is a biofilm but we are concentrating on pool water. Water mold can be an icky white-grey matter in the pool.  Many times it looks like wet tissue paper in the pool.  It is nasty, slimy and can harbor bacteria and other pathogens.  Pink slime is as the name says pink and slimy.  These are both fungus found in the pool.  They consume your sanitizer and many times cause the algae to start.  Many times you do not see these until you have treated for the algae and you may think that it is dead algae but a good indication it is not is that you cannot hold a sanitizer level.  These biofilms form many times in areas of poor circulation.  Areas of poor circulation include many hard to reach areas such as light niches, under the treads of steps, behind vinyl pool fiberglass step strips, insides of skimmers, pump baskets and throats of skimmers.   These areas should be scrubbed periodically to remove any of the biofilm from colonizing and dispersing more of itself.

 When treating for algae it is wise to try to ascertain why it bloomed so that you can adjust your maintenance to prevent further outbreaks.


Tuesday, January 3, 2012

Vinyl Lined Pools - Do You Need a Soil Investigation?

 As I was doing research recently on vinyl liner fungus I came across the International Code Council (ICC) Acceptance Criteria for Vinyl-Lined Residential Swimming Pools (AC279).  I found some of the information very interesting.  This is not information that most builders, retailers or customers ever see but I find some of it very important.     Of special interest to me is section 5.2  which states:
           

5.2

Pools and spas may be installed without a soil
investigation by a registered design professional (RDP),
subject to the code official’s approval, provided none of
the following conditions is encountered at the site:


(In most states a Registered Design Professional is an engineer or architect that has been certified and licensed by the state)

5.2.1

The existence of groundwater within the depth
of the pool or spa excavation.


(This would lead us to believe and we would be correct in assuming that once you excavate and find there is groundwater then an RDP needs to do a soil investigation to see that your structure will uphold under the soil conditions.  This cost could be hundreds of dollars.  I do not know of any builder of residential pools that does this.  Nor have I seen any code inspector inspect the excavation to enforce this.  However in years down the road and excessive underground water at any time the pool structure can be compromised causing major repairs.  I have seen this often in the area in which I serve which is a coastal community with sandy loom soil.  As shown through a school science project and shared to me by the parent who happens to be a well versed scientist, sand when wet liquifies therefore no longer bein a supportive foundation.  This can cause vinyl liners to have "sink holes" regardless of compaction during construction.)



5.2.2

The existence of an uncompacted fill in
contact with any portion of the pool or spa.


(Again, there are no inspections to test for uncompacted fill, this would be solely at the builders or homeowners descretion)


5.2.3

The existence of any expansive-type soils.
(Clay as a soil or mixed in as part of soil is called an expansive soil and is responsible for many home foundation failures.  This expansive soil can cause structural problems when used as back fill for many pool types.  In our building of pools, clay is trucked away and other acceptable back fill is brought in.  However there is usually an extra charge to the homeowner as we are doing it the correct way. Again, not knowing this as many new installers or those without proper training can cause premature failures of the pool structure.  See Expansive Soils)


5.2.4

The existence of any soil types with an angle
of repose that will not support the walls of the excavation
at desired slopes.

(This is the main reason that Fiberglass pool shells are recommended in the sandy soil areas.  If the bottom is prepared not to liquefy if water comes in contact then placement can be made and the shell supported.  It can be very expensive during and after construction of a vinyl pool if the soil will not hold shape.  A foundation would need to be made to place panels of the vinyl pool on.  Other construction materials would need to be brought in to hold the sloping walls in shape.  Engineering of how much material to be used and also dimensions are necessary to provide an adequate construction.)



5.2.5

Danger to adjacent structures posed by the
proposed pool or spa location.


(Most code officials check placement of pool to be out of the area of repose of a 45 degree angle from the foundation of adjacent structures taking into account the depth of pool or spa.  This is why engineering is required if you place the pool or spa directly next to a structure that is not on piles.)


5.2

The existence of any cracks or openings in
soil that would not confine sand bedding.

(I believe that this may be something encountered in rocky areas.  But if the sand bedding cannot be confined it would need to be engineered to show support structure)

The ICC has stated a certain acceptance level of where a RDP is needed but unfortunately in our industry this is not adhered to and not known by either the code officials or by the builders.  This is something that can add cost to the initial purchase of a vinyl pool as well.  The best protection is to work with an experienced builder that is knowledgeable in the common area soils. Work with a licensed Swimming Pool Contractor.  If your builder does not know about clay or expansive soils or can tell you what he will do and how much it will cost if unstable ground is encountered, run away and find a capable builder in your area.  It is wise to spend a little more and save lots later on.