While chemicals for your pool are certainly useful in keeping it looking great and free from bacteria, the filter is the best way to maintain a crystal clear pool. There are essentially three main types of pool filters to choose from. The options are cartridge filter systems, Diatomaceous Earth (DE) systems and sand filter systems. Each of the filter types has attributes and drawbacks to consider. You will need to take a good look at how effective each filter system is, what budget it fits into and how convenient it is to use. You will need to decide which of these criteria are the most important in your situation. While most of the filter systems cost anywhere from $200 to $1,000, they each have their own expenses associated with maintenance along the way. Here you will find information about each of the filter types and learn the attributes and drawbacks of each.
Cartridge Filter Systems
The cartridge filter system is fairly easy to use and requires little work on your part to maintain. It requires only that you replace the filter cartridge on a regular basis or wash the one that you have out. This type of pool filtration is one of the oldest having its start in the early 1950s. Most cartridge filters are made from pleated polyester cloth material. This filter material is durable and allows for long time use if cared for properly. The cartridge filter works by screening out dirt from the water that passes through it. The cartridge is housed by the filter and water is sucked in one end of the unit from the pool. The larger debris is caught in a basket outside of the filter itself, allowing only smaller particles to run through. The filter then catches tiny particles within the chamber and releases clean water back into the pool.
Different cartridges can provide different levels of collection, measured in microns. The micron size of the filter is the size of the opening between pieces of the filter media. The larger the micron filter rating the larger the pieces of particle can slip through. Pool cartridge filters are typically between 20 microns and 5 microns. The more dirt you want to collect in the filter you choose, the lower the micron rating should be. When considering the size of bacteria you want to remember that the size of bacteria runs from 0.2 to 2 microns wide. This translates into a length of 1 to 10 microns and using a 1 micron filter can potentially remove most bacteria in the water. When discussing pool filters, the job of the filter is to remove all of the small particles that it can from the pool. One example of the size of 100 microns is a single grain of salt. For ultimate filtration in a cartridge filter you will want to be sure that you obtain the lowest micron rating possible.
Cartridge Filter Care
Caring for a cartridge filter requires that you either replace or clean the filter regularly. If you purchase a filter that needs to be replaced it is important to monitor when the filter is becoming full of debris. If there is too much dirt the filter will stop being able to clean properly and the dirty water will backwash into the pool. Keeping the filter clean is the best way for it to remove as much dirt as it can. You also want to make sure that you look for any tearing and buckling in the filter as these are signs that the filter should be replaced. Some filters can last a fair amount of time when they are carefully checked on a regular maintenance schedule. Choosing a washable filter means that you can remove the filter from the housing and pressure wash it with your backyard hose. Once replaced into the housing the system will be ready to handle cleaning the water again.
Diatomaceous Earth (DE) Systems
If your primary interest when purchasing a pool filter is how well it cleans, you will want to consider the Diatomaceous Earth (DE) system. This system has the micron rating with the ability to sift out particles that measure as small as 1 to 3 microns. Diatomaceous earth is a powder made from tiny skeletal sea creatures. These sea creatures are called diatoms and died prehistorically. The tank of the DE filter has a total of eight semi-circular sections. Each of these sections is coated with the DE and a cake is formed over the sections. This becomes a micro-screen working to strain out any of the tiny particles and debris that are forced through from the pool.
Cleaning the DE Filter
The DE system requires a little work to make sure that it does the job of cleaning the pool well. Cleaning the filter is often done in part by backwashing the system. On most DE systems there is a valve to allow for backwashing. This pushes the water from the pool backwards through the filter system, thereby cleaning the filter cake. The water from the backwash is moved to a sewer drain and flushed away from the pool water to avoid contaminating the pool. From time to time it will be necessary to clean each of the filter section individually. Once this has been accomplished the filter sections will need a new coating of filter cake or diatoms. This should be done with care and a mask should be worn to avoid inhalation of the diatom powder.
In some cities and towns it is not permitted to allow the DE material flushed from backwash to go into the sewer for fear of clogging the system. This is the reason that many systems use a separation tank for backwashing. The separation tank catches the water that comes from the backwash and captures all of the DE dust and mud keeping it out of the backwash. After the backwash water has been cleaned it can either be cycled back into the pool or be sent into a sewer system, depending on the local ordinances relating to the matter. Making sure that you clean the separation tank each time that you do a backwash is vital to its efficiency. The contents should be disposed of properly in a trash receptacle. If left unchanged the separation tank will become full of the dense material and become heavy and less effective. It will also start to have a bad odor after a time.
Once you have backwashed the system and from time to time with age, you will need to add more DE to your filter system to keep it working efficiently. The proper way to handle this is by first putting on a mask to keep the dust out of your mouth and your nose. There are two schools of thought regarding how to best add the new DE to your pool filter. One way is to simply scoop the appropriate amount of DE powder into the skimmer allowing the pool filter to suck it into the filter system. Another way to do it is by mixing the appropriate amount of DE with water in a bucket and adding the water to the filter skimmer. Knowing how much DE to add is important to making sure that the filter is functioning properly. You will want to add one pound of DE for every 10 square feet of filter rounding the number up in all cases. You can either purchase a one pound scoop at the pool supply store or you can use a cup that holds 44 ounces of liquid.
Sand Filter Systems
Perhaps the oldest method of cleaning the water in the pool is the sand filter system. Dating back to the ancient Romans the process is by far the simplest to understand and use. The sand filter system requires very little maintenance to be effective. The pool water goes through small openings in a bed of sand removing particles of dirt and debris as it does. The debris is essentially trapped by the sand and remains there until the filter is cleaned. Cleaning a sand filter system requires only backwashing. Unlike DE systems there is no changing of the sand required. Backwashed water doesn’t require separation tanks and doesn’t require disposal. You simply backwash the filter and are ready to go back to normal use. Since there are no harmful sediments to be concerned with, backwashing is not harmful to the sewer or the earth. The water is simply run backwards through the filter system allowing the dirt and sediment to rise to the top of the filter system and out a backwash line. Backwashing a sand filter is fairly easy, but does require following a two part system. The first step is a simple two minute backwash. After this point you will want to allow the filter to set for 30 seconds or so in order for the sand to settle back down to the bottom so that the water runs clear again. You need the sand to be back in position before allowing the filter to run properly again. This will create the filter on the bottom of the system and is going to help you avoid any backwash of dirt back into the pool because it lets the sand trap the dirt that might be left behind again before returning to normal use. Through backwash alone the sand filter can last for many years without having to add sand or make any changes. When it comes to micron ratings, sand filter systems have the highest. In fact, most sand filters start out with a rating of 40 microns and as time goes by they actually improve to as little as 20 microns. This means that the water is not going to seem as clean at times as other pools with other filter systems. If large particles clump together in the filter you may need to use a clarifier to clear them out. This will help reduce murky looking water and allow the filter to do its best work.
You will want to keep in mind that if you purchase a filter that requires very little maintenance you will likely be saving yourself time and money in the long run. It’s important to decide what is vital to you and what you want for your pool upkeep. Make sure that you use a pool filter that is a good size for your pool. The pool expert should be able to help you decide the size that you need for your pool situation. Some pool systems will come with warranties that can also help you save money in the long run. Make sure that you consult with the professional about these options. A great pool filter can keep your pool looking crystal clear for years to come.