Maintaining a clean pool is one of the most important parts of pool ownership. In order to do so, it’s essential to have a filter for your pool. No one wants to swim in a dirty pool with dirt and debris everywhere. Swimming pool filters are a great way to rid your pool of all that unwanted material floating around. When looking at pool filters it is important to note that there are three different types to consider (Sand, Cartridge, and Diatomaceous Earth).
Deciding what type of filter is best for you and your pool can be a bit confusing. To help you through the process, we put together a comparison guide for swimming pool filters to give you a better understanding of all there similarities and differences. There is not a “bad” type of swimming pool filter, but some filters are more efficient than others. When it comes to how effective each type is; a general rule to follow is:
Diatomaceous Earth (DE): Best
DE and sand filters both are going to require a valve to control the backwashing function. The most common valves are the push-pull and the rotary valve. It’s important to note that regardless of what type, the valve should always be kept in the filter position unless another function is needed. The basic push-pull valve will only have the ability to filter and backwash. Whereas rotary valves have a greater variety with typically 6 different positions:
Filter: filters your pools water
Recirculate: circulates your pools water without using the filter
Backwash: cleans the filter tank of any accumulated debris
Rinse: rinses the tank after backwashing
Waste/Drain: sends your pools water directly out of your pool
Closed: completely stops the flow of water
As the name implies, sand filters use sand to collect the contaminants in your pool. They are large tanks that can hold between 50 and 300 lbs of sand. Sand filters work by pushing your pools water through the sand catching most of the contaminants in the water. They work best when they are slightly dirty, so a clean filter can trap particles as low as 50 microns in size, a slightly dirty one can trap particles as low as 20-25 microns. Sand filters have the ability to last up to 10 years before the sand needs to be changed.
Sand filters should be chemically cleaned as you are backwashing at least twice a year . Granular acidic crystals can be poured into the strainer basket and you will want to continue backwashing until the all of the cleaner is out of filter. It is important that you use gloves and goggles when you are adding chemicals. The backsplash of the granular acid has the ability to cause eye or skin damage.
Cartridge filters happen to be the filters of choice for hot tub/spas and many smaller above ground pools. They contain a fan-folded polyester cartridge that has the ability to collect debris as low as 5 microns. Depending on the amount of use your cartridge gets, it should be replaced every 3-5 years. However, if the cartridge is undersized it may have to be replaced ever 1-2 years. It is important to know that every time the cartridge is cleaned, it is going to lose some of its ability to collect debris. After a cleaning, the cartridge can last up to 6 months before it needs to be cleaned again. However, in most cases they will need to be cleaned on a more frequent basis.
Cartridge filters should be chemically cleaned at least twice a year. A great way to go about this is by placing them in a soak tank with a TSP (trisodium-phosphate) or a similar solution. To make this process as easy as possible, you should have a replacement cartridge on hand to place in your filter tank while the other is being soaked in chemicals.
DE filters use a white fossil powder that is coated on the grids in the filter tank to trap the contaminants in your pool. It just so happens that this powder is called Diatomaceous Earth. Before adding the DE to your filter you’re going to want to mix it with water to help it dissolve, this way it won’t clot on the grids. If the DE did clot, it wouldn’t be nearly as effective with catching the debris. These swimming pool filters have the ability to trap particles as small as 3 microns, making them the most efficient type of filter.
DE filters on pools open year round should be chemically cleaned at least 4 times a year or 2 times everything 3-6 months. Acid based and detergent based, are two commonly used chemicals for cleaning D.E. filters. If you use chlorine or bromine in your pool, you should use a detergent base cleaner first, then use the acid based. If you use biguanide in your swimming pool, you are going to want to use the acid based before the detergent based. As you remove the grids from the chemicals, they should be thoroughly rinsed off with water.
Remember, deciding on a swimming pool filter all depends on what your values are and the type of lifestyle you are accustomed to living. Sand filters aren’t as efficient as DE or cartridge filters, but they are a lot easier to maintain. If you’re someone who would prefer a clearer pool without minding the extra maintenance, then you would want to look at either a cartridge or DE filter. If you don’t care how clear your water is and just want something easy, you’re going to want to look at a sand filter. Any type of filter you chose is going to be a compromise of the filters efficiency and the level of difficulty with its maintenance. Eventually, pool filter parts will need to be replaced regardless of what type of filter you have.