Whenever the filter fills up with the dirt/debris it reduces the flow of water to your pool. Low flow = poor circulation which will lead to algae in the pool. Bottom line, the filter must be backwashed on a regular basis to ensure that your pool water is clear.
The frequency of backwashing depends largely on how much use your swimming pool gets and the type of filtration system as well as its position. If your pool is surrounded by shrubs or trees, its likely to need more regular backwashing than a pool that isn't subjected to leaf little and organic debris.
How Often Should I Backwash? A good rule of thumb is to backwash once the pressure displayed on your pressure gauge is 8-10 psi over the starting level. Backwashing after heavy rains, treating for algae, or when trying to clear cloudy water will keep your filter working efficiently.
As a rule of thumb, regardless of if you have a sand filter or DE filter, you should backwash your pool about once a week during swimming season. The optimal time is right after you vacuum the pool. If your pool has had a lot more use than normal, it may be necessary to backwash twice a week.
Can You Backwash Too Much? If you backwash your pool too much i.e. time duration and/or close frequency then yes you can cause a lot of problems. Some problems that can arise from backwashing your sand pool filter too much are: Loss of water – 500+ litres of water can be lost in each backwashing cycle.
Backwashing a filter too frequently will keep the sand so free of dirt buildup that it will not have the ability to remove the smaller particles of dirt and they will simply pass through sometimes causing cloudiness in water.
Often, excess sand gets into the wrong places when refilling and will sand to come out into the pool or out of the backwash hose. But it should go away after a few runs. In general, you shouldn't be losing sand from your sand filter. Nor should any sand be coming out during backwashing, rinsing or filtering.
Your pump may be too large or the sand level too high in the filter. When the filter is backwashing the water flow can cause the sand to rise high enough and overflow into the standpipe, which will allow the sand back into the pool.
Turn the lever to RINSE, start the pump and rinse for about 15-30 seconds. Stop the pump and turn the lever to FILTER. This is the normal operating position. Close the drain outlet valve and start the pump.
Add diatomaceous earth (DE) to your pool skimmer, stick to around a scoop or two – no more than the size of a 1lb coffee cup. The moment you do this, go to the pool jets to see if it is returning DE into the pool, or if the water suddenly looks cloudy. If it is, you likely have an issue with your filter.
Overall, the lessons learned today is you should run your pool pump an average 8 hours a day to properly circulate and clean your water. The pump should push your entire pool in gallons in this 8 hour period of time. Residential pool water only needs to be turned over once daily to have proper filtration.
Rinse runs water in the same direction that normal filtering does. Backwash runs it through the sand in the opposite direction. Rinse is to clear any dirt out of the clean side of the sand before you start sending it back to the pool.
It is not recommended to drain a swimming pool through the backwash valve. While sucking from the main drain and putting the water down the backwash line will work in some scenarios it puts your pool pump at risk of losing prime and running dry.
Bottom line, the filter must be backwashed on a regular basis to ensure that your pool water is clear. "When do we need to backwash?" - It is recommended to backwash your filter once every 4-6 weeks of regular use.
If you do have this option, it is highly recommended that whenever you have algae, you will need to vacuum to waste. This option allows you to vacuum the algae up and send it out through the backwash line, avoiding getting algae into your filter sand.
Small amounts of DE can be added to a sand filter after each backwash to improve the filtering. The first time you use DE, you need to figure out how much DE to add to your filter. After the first time, you can simply mix the full amount of DE with water in a bucket and pour that slowly into the skimmer.
Too much sand and your filter will likely not run correctly or may break when reassembling. Too little sand and you will have cloudy water no matter how much your filter runs. For this reason check your filter manufacturer's specs.
Rinse. The 'Rinse' setting should be used after backwashing and again run just for a minute or two. On this setting the water is flowing through the filter in the normal direction but once again is being sent to the waste pipe rather than being returned to the pool.
How Much Sand to Add to Pool Filters? Sand filters are not filled completely full of sand, but only about 2/3 full, to allow “Freeboard” space in the tank, above the sand bed.
How often will that be? The sand in your pool filter needs replacing every three to five years, sometimes even longer if your pool remains in relatively good condition when it's open. If you run your pool filter often all year and have a heavy bather load, the sand may need replacing sooner than three years.
The size of your pool, the efficiency of your pump and filter, and how dirty your pool is are just some of the factors you need to consider. Nevertheless, most pool cleaning professionals would advise against running a pool pump for more than 8 hours a day.
It may be cheaper to run the pump at night, but honestly you should run it 1 hour a day per 10 degrees of temperature at least, and it should be during the day. Running the pump at night should only be when you are doing a major chemical treatment such as algae clean-up.