Most pool owners know how to maintain their swimming pools, and they do a jolly good job. However, most don’t know why they do the things that they do in order to keep their pool looking pretty. Sand filters may not be a thrilling thing to discuss, but wouldn’t you like to know more about the operating system of your pride and joy?
How Do Sand Filters Work?
The cover of your pool pump and filter system tends to hide the clever systems which work busily to keep your swimming pool clean and hygienic. However, you’ll be interested to know that the filtering of water stretches as far back as ancient Egypt where the use of porous clay bowls was commonly used to filter drinking water. Various grasses have also been used to sieve water to separate out debris. Gravel, charcoal and sand are still used today in water purification devices in the home.
But, you may ask, “Surely the chemicals in my pool keep it clean?” Certainly. The chemicals that you add to your pool kill harmful bacteria and prevent algae from developing. But what they can’t do is remove the actual debris from your water. This is where your filter comes in.
Sand filters are an inexpensive and durable choice for swimming pools, making use of a special, fine grain sand to trap particles as small as 0.02 mm.
Dirty water is fed into the filtration system through the inlet pipes which can be either from the wall mounted inlet where the skimmer will usually sit, or from the pool cleaner which sucks water and debris up from the sides of the pool. Either way, larger particles such as leaves, insects and other debris are caught in the net, and the rest of the water is fed into the tank.
Gravity pulls the water through the sand in the tank, trapping small particles and expelling the clean water out the other end. Obviously, the larger the volume of water in the pool, the stronger the pump and the larger the sand tank would need to be.
Cleaning Your Sand Filter
It stands to reason that all the dirt and debris collected over weeks and months will eventually start to clog up the sand filter, and you may find that the pump is not working as efficiently as it once was.
It’s time to backwash. Reversing the flow of pipes allows pool water to be pushed upward through the sand and runs off into the sewer or into your garden. Yes, this does waste a fair bit of water, but it’s the only way to clean the sand and get your system working again.
So now you know how your sand filter works in your pool. If you have any questions or need any help in maintaining your swimming pool, we’d welcome your call.