Reverse Osmosis for Swimming Pools

We have been successfully doing Reverse Osmosis (RO) purifications to swimming pools for over ten years and appreciate everyone who has embraced the process and chosen to go this route instead of draining and refilling.  Our goal has always been to provide honest and accurate information as to what RO can do and what to expect from the process.  We read a lot of articles online and it seems that there is still quite a bit of confusion as to how well RO works or its costs, so we decided to try to address these questions in this post.

1. Reverse Osmosis is not new and is an option for draining and refilling a swimming pool. While it is somewhat new to the swimming pool industry (we built our first trailer in 2009), the RO process has been around for decades.  Inefficient RO systems abound (these are typically under-the-counter systems that work on house water pressure, which sees a lower recovery and more waste) but systems designed with proper pressure return great recovery rates, and our systems return up to 85% recovery.
2. Reverse Osmosis removes excess minerals and so much more from swimming pool water. Certain areas of the country struggle with high calcium content, whereas other pools are just overloaded with salt or conditioner.  Some pools are high in phosphates or copper, and some pool owners are looking to have all of the above addressed.  Did you know that RO also removes or lowers bacteria, viruses, nitrates, etc.?  Did you also know that RO does not remove unwanted pool guests, nosy neighbors, or pool noodles that were left in the pool?  While RO does a fantastic job at making incredible water it does not do everything!
3. Reverse Osmosis allows you to use your pool during the process. Where a drain and refill may take days and put your pool out of commission, an RO treatment can be done while you swim or enjoy your pool.  In addition, the pool’s interior surface (be it plaster, pebble, vinyl, or fiberglass) does not get exposed.  Most of these finishes have been wet their entire life and do not like to be out of water, especially in high temps.  In the case of plaster, it can (and does!) contract when exposed to the air and expands again once water is reintroduced.  The finish can only take so many expansion and contraction cycles before it tries to delaminate.  Another benefit of RO is keeping the water weight in the pool and therefore keeping the pool in the ground.  Removing the water weight in some pools can cause them to float out of the ground, and they will not go back in after this occurrence.
4. Reverse Osmosis does have its limitations. Commercial operators love our ability to purify their pools (did you know that we have systems that can be mounted inline and operate behind the scenes, always keeping a pool within a certain water quality range?).  Whenever there is a swimming pool with a high bather load, the opportunity for waterborne infection increases.  While RO is capable of minimizing this opportunity, there are instances where the pool will still require a shutdown (a “Code Brown” incident is a great example) and we must realize that RO is not a silver bullet for all situations.  Another example would be a customer with a heavy algae-filled pool (this is a chemical or circulation imbalance or a combination of both) and RO does not like algae.  That said, algae blooms are typically easy to clear, and then RO can come in and finish the job!
5. The myth that Reverse Osmosis is too expensive truly needs to be clarified. We hear this not only locally but in some of the online forums that we frequent, and it is usually just a lack of knowledge (shame on us for not doing a better job here!).  In our area of the country (San Diego), we are very competitive with the cost of water and a pool tech doing a drain and refill.  In other parts of the country, we know that our Service Providers are cheaper than a drain and refill.  The cost of RO versus a drain and a refill also needs to take into consideration downtime, water quality, liner exposure, the potential for the pool to float out of the ground, and more.  Some folks are more DIY and will choose to drain their pools, while others appreciate the water quality and lack of hassle that RO treatments provide.

Obviously, as the Reverse Osmosis guys, we never advocate draining and refilling a swimming pool (an exception would be when it is time for a re-plaster), but we know that some people will still opt for this.  We understand this but we also wanted to provide some knowledge as to what RO is capable of.  While Reverse Osmosis (Puripool Process) purification will almost always provide superior water to what can be purchased, it is also hassle-free and risk-free.  So when you consider taking the time and effort, as well as worrying about what can go wrong during a drain and refill, you may want to ask yourself why you really wouldn’t call us or one of our Service Providers and schedule a Puripool Process; we know you will be happy you did!