Pool water filtration is one of the most important aspects of a swimming pool. For obvious reasons, it is imperative that the water be clean and clear. Swimmers and lifeguards require this crystal clear water for several reasons, whether it be for swimming laps, knowing when to start a flip turn, or being able to see all of the pool patrons clearly in order to effectively monitor the pool. Furthermore, the water needs to be clean and free of bacteria so that swimmers do not leave with an illness. While there are many systems that work in conjunction with a pool filter to help keep the water healthy, the physical pool filter, which is available in varying styles and options, is the focal point in providing clean, clear water.
In most cases, pool water is pushed by the filtration pump through the filter system. Other systems operate using the pump on the other end of the system where it can pull the pool water through the filtering system. Either way, what happens is essentially the same – as water passes through the filter media, physical dirt and bacteria are removed, and clean water continues from the filter through the remainder of the recirculation system for further treatment, and returned to the pool.
The style of filter, along with the media being used, will determine the effectivness of the filtration system, as differing types of filter media actually filter different sizes of particles out of the water.
#20 SILICA SAND
The reason that pool filters use #20 silica sand (also known as 20 grit or 20 grain, 0.45-0.55 mm sized granules) is that it is small enough to filter out micro bacteria, yet large enough that it doesn’t get pushed through the whole plumbing system and cause other problems. In addition, larger granules are unable to filter the small bits of dirt and bacteria that it is intended to. #20 silica sand can filter out particles down to 20-40 microns in size. As water passes through the sand (which is essentially a really small stone, which is jagged on all edges if looked at through a microscope), the jagged edges catch tiny dirt and bacteria particles, eliminating them from the pool environment.
Depending on various factors (bather load, bather cleanliness, etc.) sand filters need to be backwashed every so often to clean the sand. If the sand filter is not maintained, it will stop filtering as it is supposed to. Backwashing is completed by running water through the system backwards to release all of the dirt and bacteria that has been caught by the sand, and must then be removed from the filter tank. When the water being discharged is clear, you are finished backwashing. Most filters have a sight glass so operators can physically see the dirty water at the beginning of backwashing eventually turn clear when the process is done.
Sand is the oldest and most commonly used filtration media, because it is effective and one of the most cost friendly options. However, after many cycles of filtering and backwashing, the granules become rounded, eliminating their filtering capabilities. The sand should be changed approximately every 5 years, depending on usage and backwashing frequency.
Zeolite is an all-natural product that is gaining popularity in the pool industry. It is about half as dense as #20 sand, meaning you can use about half as much as what is recommended for the filter. For example, if your filter requires 100 lbs. of sand, you would only require about 50 lbs. of zeolite. This type of filtration media is a bit more expensive than sand, so there will be a higher upfront cost. With the ability to filter particles down to 5 microns, Zeolite is comparable to a D.E. filter, and better than sand, though D.E. filtration systems are much more expensive than a sand filter system charged with a zeolite media. Zeolite lasts about the same amount of time as sand with regular use, which is approximately 5 years.
Crushed glass is a new addition to the filter media family. Made from recycled glass (good for the environment) that is crushed to the same size as #20 sand, it filters using the same principles as sand. In comparision to sand, crush glass lasts longer (approximately 10 years) and can help in removing micro particles with its negative charge. When using crushed glass, more of the filter media is used for filtering because it utilizes more of the filter tank, as opposed to sand which typically only uses the top four to six inches. This means there is a shorter backwash time, saving more precious water.
DIATOMACEOUS EARTH (D.E.)
Diatomaceous Earth (D.E.) filters the water very effectively, down to two to six microns, however they are more expensive systems and take up a larger footprint in the mechanical room. D.E. is tiny fossilized skeletons of sea plankton that are coated onto a grid of filter elements that sit in a tank where the pool water passes through. The water can either be pushed or pulled through this system. D.E. is considered carcinogenic, and proper handling and storage techniques, including protective gear and breathing protection, must be adhered to. D.E. filters are able to be backwashed for cleaning, but the media is lost in the process, and needs to be periodically replaced. D.E. systems do not eliminate chloramines which cause the chlorine smell commonly noticed at an indoor pool, so using a UV system is strongly recommended in order to eliminate them (a reccommendation for all pool filters).
Regenerative filters are another new option in the pool market. They also utilize D.E. or a synthetic substitute, however are a bit more complex in their design. In a traditional D.E. filter, only the channels and depressions of the surface of the filter media trap particles. The underside of the D.E., the side attached to the grid, has a reduced ability to filter. In a regenerative filter, the media is held on multiple tubes, or “fingers”, that are periodically “bumped”, causing the filter media to fall to the bottom of the tank. The filter media is then redistributed, allowing unused sides of the media to be used for filtration as well. Regenerative filters offer a large amount of surface area with a relatively small footprint and are often toted for their water saving qualities due to the reduced need for backwashing and D.E. replacement. The water savings may or may not offset the cost of these units, therefore your individual return on investment should be evaluated before purchase.
Thanks to several innovations and advancements in technology, there are many options available when considering pool filters, and filtration media. It is important to consider all of the factors specific to your project when choosing a filtration system, or to at least understand what you want and don’t want when planning with the pool designer that is working on your project. You want to have the right filtration system and media for the facility to ensure it is operating in the most economical way.
Heat Loss Prevention: Solar Blankets or Liquid Pool Covers?
Wednesday, July 11, 2018
When I think about heating an outdoor swimming pool, the first method that comes to mind is a solar blanket, or solid cover. Usually, this means a large blue bubble wrap sheet that covers the entire surface of your pool, and is stored on a reel when the pool is in use. However, did you know there is another option to help keep the heat in your pool? Let’s take a look at two of the most common, but different options.
A solar blanket retains heat, and radiates the heat to the pool water when the sun is shining. When purchasing a solar blanket, you have several options you can choose from including, but not limited to size, shape, colour, density, and type of material. With the array of sizes and shapes, there will always be something that will fit your pool almost perfectly or, in some cases, after a little trimming. All colour options are equally effective, so the choice of colour is ultimately based on the pool owner’s preference. The density of the cover will usually determine the life expectancy of the cover.
Solar blankets can help protect your pool water from debris that could blow in on a windy day; however, solar blankets can also become a breeding ground for algae if left on for too long in the heat and humidity. Below, are a list of some of the advantages and disadvantages of solar blanket heating options.
Solar blankets have an insulating quality (provided by the air pockets that make them up) that liquid covers do not.
Can help prevent some debris from entering the pool
Solar Blankets don’t last long. After approximately 3 seasons, the blanket will need to be replaced.
Labour intensive (If you do not have a reel for your solar blanket, you need two sets of hands to lift and fold the blanket before and after pool use)
Solar blankets are not aesthetically pleasing.
They can be very dangerous if trapped underneath.
Not environmentally friendly. Did you know you can make tens of thousands of sandwich bags from the material used in a solar blanket? Process to manufacture uses oil to produce the plastic.
Although a solar blanket will prevent some debris from entering the pool, most of it ends up in the pool when you take the cover off.
LIQUID POOL COVERS
Liquid covers reduce heat loss in your swimming pool by reducing evaporation of water from the surface. There are a number of liquid pool covers currently on the market by many different manufacturers. However, one thing that seems to be consistent throughout the market is the environmentally friendly factor. Liquid pool covers are usually biodegradable and made with an alcohol based product, which won’t harm your pools chemistry when used in the correct dosage. Most importantly, liquid pool covers are safe for your family, and even your four legged friends!
The ingredients used to form a liquid pool cover are not the only safety feature. When considering safety, liquid pool covers are by far the safer option in comparison to a solar blanket. If you have children or pets and use a solar blanket, there is a potential risk of entrapment. Once submerged, a solar blanket can be difficult to escape for people and animals of all sizes. A liquid pol covers invisible film is impossible for something or someone to get caught underneath, eliminating the risk of entrapment entirely.
When taking operation into account, liquid pool covers have their disadvantages as well. Since the liquid is a thin layer, it can be disturbed by movement in the water and from wind. The liquid pool cover will only resume its total pool coverage once the water movement has stopped.
The convenience of a liquid pool cover is another benefit. There is no labour required to use this product. On top of that, how many times have you thought to yourself, “I’d like to go for a swim”, only to realize that your solar blanket is on and to go swimming, you not only have to find another set of hands, but you also have to remove it? Sometimes, going for a swim isn’t really worth the effort. A huge benefit of a liquid pool cover is the immediacy. Do you want to swim right now? Great! With a liquid pool cover all it takes is a big jump and you are swimming, without the worry of lugging that large wet plastic tarp off of your pool. Below, are a list of some of the advantages and disadvantages of liquid pool covers.
The danger of entrapment is eliminated with the use of a liquid pool cover
There is no labour requirement
No need to worry about replacement covers
Very aesthetically pleasing. The cover is completely transparent, and invisible to the naked eye. Swimmers won’t even know it is being used.
Environmentally friendly and biodegradable
Must purchase the product
Not suitable for disturbed water
Will not stop debris from entering the pool
Solar blankets and liquid pool covers both have their benefits, but they also have their downfalls. They are both effective at preventing heat loss from your pool, however, there are some differences. After considering all of the factors for each option, and weighing them against some of your needs you can determine the benefits you value the most, which in the end, will help you make a decision.
Today, technology is all around us. It makes our lives easier and allows us to connect to anything from anywhere at anytime. Having a smart phone, access to the internet, and heck - even a personal computer, is a staple in this day and age. The internet is about to become classified as a utility because we are so dependent on it for our everyday life. When I was growing up, technology was nowhere near where it is today. There was no such thing as an iPhone, an Android phone, or a Blackberry. I remember the days when a telephone was attached to the wall, it had a rotary dial and a cord, and it meant running half way across the house to answer it when someone called! The extent of modern technology in my house as a kid was a microwave, a television, a VCR and an Atari game system. If I wanted to communicate with friends I had to either call them on the old rotary phone or walk down the street to their house.
Fast forward to 2016 and just imagine your life without technology. With app’s like Twitter, all of the day’s news is waiting for us in the palm of our hand each morning. With Facebook and Instagram, we don’t even need to call our friends to know what’s happening in their lives. Technology has so much to offer and it has reached out into most areas of our everyday lives making completing daunting tasks more efficient and less time consuming. If you look around, how many people do you see without a form of technology, whether it be a mobile phone, a tablet or a personal computer?
Well the modern day swimming pool is no different. Technology, automation, and computer controls play a very important role in today’s pools. Gone are the days of having to manually adjust the chemistry in a swimming pool by hand on a regular basis. Swings and spikes in pool chemistry were difficult to control when adjusting manually, but with the help of technology, computer controls keep the chemistry in check and allow your pool to virtually run on auto pilot.
These improved chemical controllers also add an additional level of safety to the modern pool. Given that the chemical controller controls the feed of chemicals into the system, it also has the ability to lock out the feed if chemical levels get to high or too low. For example, if the PH level in a pool drops too low, the water will become very acidic and can cause damage to the pool/spa, and can also cause irritation to a swimmers body. If the body of water is very small, such as in a spa, and PH levels are drastically low, it can even cause acid burns. When the controller sees a low PH condition it will put the controller into alarm and prevent additional feeding of muriatic acid, keeping bathers safe and alerting the operator through on screen displays, texts or email notifications. The controller can also do the same thing when it comes to chlorine levels. If the chlorine levels in a pool or spa become too high, it can lock out the chlorine feed until the levels come within an acceptable range. The controllers can be set to a proportional feed, pumping in smaller amounts of chemicals to prevent “over shooting” or “spiking” chemical feed.
Behind the scenes of every swimming pool is a mechanical room; the mission control of a pool. The mechanical room is full of pumps, filters, piping, heaters, controls, UV’s, and a small computer control center called the chemical controller. The chemical controller is the brain of the entire operation, but what does it do and what are the differences between the different manufacturers?
The chemical controller constantly monitors the water through a sample line and sample cell which is fed water via the filter pump. The basic controller is checking the chlorine or bromine levels and PH with ORP and PH probes. Higher end controllers also have the ability to check free chlorine, total chlorine and stabilizer levels. What’s more, they can also connect to and control UV units, start and stop filtration systems, automatically control backwashing of the filters and they can even communicate with variable frequency drives (VFD’s) and building automation systems.
The days of worrying about your pool while you’re off duty or away from your facility are long gone. With new technology, most chemical controllers now have the ability to send a text or email notification directly to your smart phone if the controller senses a problem! You can even connect to them over the internet through HTML or smart phone apps to monitor and control the complete system from anywhere in the world. Talk about a technological advancement for a swimming pool!
Imagine being a pool operator of a commercial facility and having an issue with the pool in the middle of the night, or worse, while you are away on vacation. You could come back to a real mess, and the pool chemistry could be completely out of balance. Depending on the size of the pool, this mess could take a couple of days to get back inline. A pool with a modern chemical controller will notify you of the problem and then automatically start to chemically treat the water to keep it in balance, before you come back to a big mess.
But what are the big differences between different manufacturers? Is one better than the other? In my opinion, there really aren’t any “big” differences; they all come down to budget, options, and operator preference. All name brand controllers come with the basic ORP and PH monitors and controls, and just like a new car you can get them with options. For example; if monitoring the chlorine levels and bromine levels by ORP is not your thing, add on a PPM probe. Some operators are not familiar with ORP levels, but they are very familiar with PPM levels because this is what they commonly record in their books. Is the ability to log in and control your pool using your smart phone from anywhere in the world important to you? No problem! Just add an HTML interface. Today, most chemical controller manufacturers are seeing the importance of being connected all the time and this option is now becoming a standard hardware option and just requires setup at the time of commissioning. Are you looking to monitor the cyanuric acid level of your outdoor pool? No problem! Simply add on the probe. Free chlorine and total chlorine are an easy add-on to any system with the simple addition of monitor probes. All of these options can be added to any chemical controller.
No matter what brand you choose, at the end of the day all will ultimately do the same thing. How much it will do depends on how much you want to invest and what options you want to include.
So next time you are staying up to date with your friends on Twitter and Facebook, or checking the news on your CNN app, take a few minutes to click the pool app on your phone and see how things are operating on your swimming pool.
Salt Water Chlorination: Is it the Right Option for your Facility?
Wednesday, March 14, 2018
Salt or no salt? That is the question! Or at least one of the most common questions being asked by pool owners and operators these days. Every pool owner has their own set of reasons for wanting salt or not wanting salt. There are many questions regarding the mechanical equipment at the facility, finishes of the pool, uses of the pool, local bylaws, (just to name a few) that must be answered before jumping to any decisions. Additionally, the owner must be aware of the many myths regarding salt water systems and chlorine systems alike before making any decisions. They must also understand that a salt water pool doesn’t mean you will be swimming in ocean water! Windows to the Universe team states that salt water pools typically have 3,000 to 6,000 ppm, while the ocean is about 35,000 ppm.
When changing a liquid chlorine sanitized pool over to a salt water system, or when building a pool destined to be salt water, the mechanical systems must be selected properly. Everything from the pumps, filters and heaters must be designed and approved for use in a salt water pool. If this is not done, manufacturers will not honour warranties, and there will be damaged equipment much prior to their normal lifetime.
The finishes of the pool need to be considered when contemplating a salt water pool as certain finishes do not last as long under salt water conditions. Liners, tile and plaster finishes all have their own issues when it comes to salt, so owners must investigate each option thoroughly and ensure whichever option is chosen is installed properly. As with any sanitation system, monitoring and proper balancing is also very crucial in the lifetime of the finishes.
Fixtures such as hand rails, underwater lighting fixtures, and rope anchors need to be properly chosen when going with a salt water pool as they will corrode faster without being constructed of proper materials and properly maintained. The image above shows a hand rail in a salt water pool that is rusting due to the salt. Think of what salt use on our roads does to our vehicles and infrastructure during the winter months. The same type of damage will happen to a pool that doesn’t have all of its components designed for salt water use.
Primary uses of the pool under consideration for salt water should also be considered. A pool that is primarily for lap and competition swimming where there is high swimmer volume and high exertion may want to shy away from a salt system, as it will require much more monitoring of the chlorine levels to ensure they are in accepted ranges. Yes I said chlorine. Salt water pools still have chlorine in them. They use a chlorine generator system involving a process called electrolysis to produce its own chlorine, rather than adding liquid chlorine directly to the water. A therapy pool with low patron turnover may be a better candidate for salt water, as it will be easier to keep the pool balanced and may increase user comfort.
Local bylaws are another very important item to look into when considering salt water in your pool. Especially for commercial pools, salt is typically not permitted to be the primary source of sanitation. Most municipalities still require salt water pools to have a secondary sanitation system installed, typically liquid or tablet chlorination. Furthermore, when draining the pool, salt (and chlorine) levels usually must be brought down to low levels in order to legally be dumped into the municipal sewage treatment system. Always check local bylaws for your stipulations prior to draining your pool.
Pool owners need to ensure that they do as much homework on salt water chlorination as necessary to ensure that they have made an informed decision. There are too many cases of owners not taking all of the necessary steps required to properly operate a salt water pool, and have a seemingly endless repair bill. As with any large expenditure, always ensure you are working with qualified pool designers and builders when constructing a new pool or doing a renovation, no matter what sanitation system you are going with.
When planning the construction or renovation of your pool, whether commercial or residential, one of the many decisions you will need to make is the pool finish. There are several options available to both commercial and residential pools, there are also many factors to consider when choosing a finish. Cost is usually the first thing on everyone’s mind, when making any purchase. However, there are many other considerations that will often times outweigh the initial cost. The intended use of the pool is an important factor to consider when determining the finish of a pool. Residential pools, which have a lower use, can get away with one of the more budget-friendly options, as there is less wear and tear. A low-cost finish will save some money upfront however, repairs and refinishing will be required much sooner than some of the longer lasting, high-end finishes.
Tile has been used as a pool finish for years and is known to be the most durable finish. When applied correctly, a tiled finish can last for decades before requiring any replacement. Tile offers the pool owner a wide variety of colour options and design possibilities. Due to the preparation and labour required for installation, this high quality finish option comes at a higher initial cost. However, over time it will pay for itself, through the savings on repairs and replacements.
Durability & Longevity: A tiled finish will last decades if applied correctly, and compensate for the higher upfront costs.
Easy to Repair: If there is an issue with isolated delamination of tile, it is very easy to replace small areas of tile and match to the existing, without having to re-finish the entire pool.
High Upfront Cost: Correctly installing tile, comes with heavy labour including; the preparation of the subsurface, laying the tile and grouting the tile.
Deterioration of Grout: Though tile has a very long life span, the grout will deteriorate much quicker. Over time grout will begin to wear out of the joints and discolour. Normally, grout will be required to be replaced much sooner than the tile.
Plaster is one of the most prominent pool finishes around, and has been used for several years; a quicker install than products like tile is the main reason for its popularity. Plaster is shot onto the pool walls, similar to gunite, and then toweled to give it a smooth consistent finish. A plaster finish does require some sort of tile border at the waterline as the waves against the plaster will cause it to deteriorate quickly.
Cost & Durability: Even with the high level of durability a plaster finish offers, the cost is relatively low.
Aesthetically Pleasing: Plaster provides a very nice finish which is smooth and able to form to any shape or design.
Pool chemistry can very quickly deteriorate a plaster finish if not properly maintained; low pH in the water is a big concern and requires experienced supervision.
With age, pool plaster will start to delaminate and cause sections of the plaster to pop off, having to re-plaster a pool is very costly.
Painting a pool is a very inexpensive method of finishing any pool, and is typically used in a commercial application for community or public pools. Though painting a pool is an economical and quick finish option, over several years the paint will chip and need to be repainted. A parge coat is required before painting to ensure all honeycombing of the concrete is filled, leaving the floor and walls smooth.
Low Cost & Project Schedule: The cost of the material and labour required to complete the work is extremely low and can be completed quickly.
Low Risk of Damage: Since paint is applied to a cementations backing, there are no concerns about damaging or puncturing the finish from items in the pool.
Frequency of Repairs: A paint finish will need to be refinished every 3 to 5 years, requiring the existing paint to be blasted off before repainting.
Imprefections: If the subsurface of the pool is not done perfectly any imperfections such as honeycombing or rough parging will show through and can cause injuries to swimmers.
VINYL LINER FINISH
Traditionally Vinyl liners have been a typical residential pool finish, due to the relatively low cost and quick installation. Liners can and have been used for commercial applications however, due to the low durability of a liner it is not very common. Vinyl liners can be used in both stainless steel and concrete pools.
Low Cost: In comparison to other finishes, liners can be an economical alternative. The liner itself is relatively inexpensive, in comparison, and installation labour is a significantly lower cost.
Creates a Water Tight Tank: This benefit can be an efficient solution, saving time and money, to a deteriorating concrete pool, which has started to leak.
Deterioration: Vinyl liners are more susceptible to deterioration caused by harmful UV light and poor water chemistry, resulting in the liner needing to be replaced sooner.
Easy to Damage: Vinyl liners can very easily be damaged from foreign objects, such as tree branches or toys falling into the pool. Punctures in the liner will result in water getting behind the liner, causing the pool to leak and the liner to bubble out.