What Is A Pool Skimmer? How does A Pool Skimmer Work?

There are essentially two types of pool skimmers. One type has a net attached with a long pole which is used to manually remove leaves and debris out of a pool. The other type is built-in as part of the pool filtering system to remove debris and leaves.

They are both important and have similar functions for keeping a swimming pool clean. I will be explaining how they work, how to use them and how to care for them.

What Is A Pool Skimmer?

Pool skimmers are rectangular plastic inserts, that fit into the upper side of a pool wall. They contain a weir and a basket which has lots of small holes in it. A pool skimmer stops and traps large leaves and debris from reaching the pool pump and filter. This is the first stage of filtering in a swimming pool filtering system.

On top of the skimmer, there is a hatch or lid where you can gain access to the basket. Within the skimmer on top of the basket, there is a detachable lid with a hole in the middle that allows you to connect a hose for manual and automatic vacuuming.

The other type of pool skimmer is the one that floats and moves around on top of the water and has the same function as the built-in pool skimmer.

How Does A Pool Skimmer Work?

A Pool Skimmer is the starting point of a swimming pool filtration and circulation system. There is a suction pipe located at the bottom of the skimmer underneath the basket. When the pool pump is on the pool water is drawn through the skimmer towards the pool pump causing a suction.

The Pool Skimmer uses a mechanical skimming action that works with the pool water level and the flow of water over the weir. Water is drawn into the skimmer which moves over the skimmer flap (weir). The skimmer flap (weir) adjusts its self automatically according to the pool water level and suction of the water. As the water moves over the weir the speed of the water increases causing a skimming action, thus pulling any debris and leaves with it.

From there the water passes through the basket on its way to the pump and filter. The basket has holes in it which trap leaves and debris that are bigger than the holes of the basket.

This is the pool filtering system’s first line of defense to trap bigger debris before it enters the pump and main filter. Therefore allowing the main filter to filter only the smaller contaminants from the water. Without a pool skimmer, the main filter will get blocked very quickly.

When the pool pump is off, the skimmer flap (weir) moves vertically and closes off the skimmer inlet hole thus preventing any debris and leaves from reentering the pool.

Another helpful addition to the skimmer basket is a pool skimmer sock.

A Pool Skimmer Sock allows the skimmer basket to trap even finer debris. A pool skimmer sock comes in handy when you have a green pool full of algae. The sock traps the algae before it blocks the main filter.

When you are filtering a green algae pool, you will need to replace the skimmer sock a couple of times depending on the severity of the algae bloom.

What happens is that the skimmer filter sock has small holes and will get clogged very quickly. Therefore causing a restriction on pool pump flow which creates air in the system. There will be no movement of water, therefore, no filtration and pump damage can occur. Be present when using skimmer filter socks with a green, yellow or black algae pool. If your pool has a skimmer equalizer line built-in then you won’t have this problem

These filter socks stretch over the top of the skimmer basket. They are made from a strong flexible ultra-fine mesh material.
The filter socks are designed to trap small debris like hair, pollen, algae, oil, grass, bugs and any other debris before it reaches the pump and filter.

Giving longer service life to the pump and filter. When the socks become blocked they are designed to be washed out and reused many times over.

Do not dissolve chlorine tablets in the skimmer basket when the sock is on as they erode the sock.

Types Of Pool Skimmers

In-Ground Pool Skimmer

In-ground pool, skimmers are surface skimmers made from durable plastic (or PVC) or precast concrete. The skimmer is built with a tank and an opening on the upper side. They are placed on the upper part of the pool wall. The swimming pool water level usually fluctuates between half and the bottom of the skimmer opening. More than one skimmer can be added to a pool depending on its water capacity.

The positioning of in-ground pool skimmers in relation to the return jets is critical for pool circulation.
In-ground pool skimmers have a movable flap called a weir. The weir opens or closes according to the pool’s water level and flow of water. The weir will open when the pool pump is on.

The weir creates a skimming action ( increase in water speed) as a thin layer of water flows over it, pulling floating leaves and debris into the skimmer basket.

When the pool pump is off the weir closes and traps the debris in the skimmer. Debris cannot flow back into the pool.

It is good practice to remove and clean the skimmer basket of debris at least once a day. Being blocked it can put an unnecessary strain on the pool pump.

An in-ground skimmer should have an equalizer line installed. This helps to prevent air from entering the system if the water level drops too low or the skimmer basket gets blocked.

Above Ground Pool Skimmer

Above-ground pool skimmers either hang off the side of the pool frame with a bracket or they are free to float on top of the water.

Depending on the above ground pool brand, there might be a precut opening in the pool liner for an integrated pool skimmer to be fitted. It is now becoming popular to fit these integrated skimmers to above ground pools.

The only thing here is you would need to cut the hole in the liner correctly otherwise the whole pool liner will have to be replaced. This is either a DIY job or if you are not confident have a pool specialist to install the skimmer for you.

Automatic And Solar-Powered Pool Cleaners

The automatic and solar-powered pool cleaners are becoming increasingly popular with pool owners.
The automatic cleaner works with the return jets of the pool.

An automatic cleaner is connected with a pipe to the return jets and how it works is that as the water gets returned from the pump back to the pool it first enters into the automatic cleaner basket where the water is forced to rotate like a whirlpool. Then sucks the surrounding water and debris into the top and down into the filter bag. The debris gets trapped in the filter bag and the water returns back into the pool.

This helps to reduce the load on the suction skimmer and weir, which in turn cuts down on the load of the main filter. Unfortunately, it only works when your pool pump is switched on.

A solar-powered pool cleaner works on solar power and internal rechargeable batteries. The batteries are charged by the sun’s energy during the day which powers the cleaner. The solar-powered cleaner can be used for in-ground and above ground swimming pools.

A small electric motor drives a rear paddlewheel to move the cleaner through the water, while a front paddlewheel scoops the surface debris into a collection tray. The rechargeable batteries allow the solar-powered pool cleaner to work in overcast weather conditions, in the shade and even after sundown. The cleaner shuts down automatically when its charge reaches a certain level. The cleaner stays like this until it gets enough sunlight to power up again.

Certain solar pool cleaners have a chemical dispenser built-in to take pool chemical tablets. This disperses the chlorine or clarifier chemicals more evenly in the pool. Thus being more effective.

When To Clean A Pool Skimmer Basket

Your pool skimmer is the first line of defense within the pool filtration system. You don’t want the skimmer basket to get to full and then not cope with the debris it has inside it. Eventually, that debris will get soft and broken up into smaller pieces and sucked into the main filter.

How often you need to clean out the skimmer basket also depends on weather conditions and what type of plants and trees you have close to the pool. Neglecting skimmer basket cleaning will give you more work in the long run.

The big question is how often should you clean out the skimmer basket. My answer is once a day. If you have two skimmers clean both out daily. When you clean the basket out you will be able to keep track of what debris is in your pool.

When the skimmer basket gets cleaned daily there is less chance of debris getting to the pump and main filter as well as extending the life of the pool pump as it won’t have to work so hard when the skimmer basket is full and restricting pump flow.

How To Clean A Pool Skimmer

  1. Firstly turn the pool pump off.
  2. Then remove the cover of the skimmer to gain access to the skimmer basket.
  3. Either your skimmer will have a turn-lock so remember to turn the basket counter-clockwise before removing. Or the basket just pulls straight up.
  4. Empty the skimmer basket and it is advisable to spray all the small debris that sticks in the holes out with a garden hose.
  5. Replace the basket back into the skimmer and turn the basket clockwise if you have the turn-lock type.
  6. Replace the skimmer lid and turn the pool pump on.

How To Clean A Pool Pump Basket

Firstly turn off the pool pump.

  1. If your pool pump is below the pool water level. Turn the multivalve position to CLOSED.
  2. Block the return jets with a plug.
  3. Remove the skimmer basket and block the hole with a plug.
  4. Now no water can gravity feed from the pool to the pump.
  5. If your pool pump is above the water level then skip step 2.
  6. Remove the pool pump lid turning it counter-clockwise.
  7. Take out the basket and clean it thoroughly with a garden hose.
  8. Inspect the basket for cracks and holes as they are plastic and become brittle over time. (Replace Basket If Necessary.)
  9. Inspect the pump lid o-ring for cracks or tears. (Replace If Necessary)
  10. Replace the basket into the pump. You may add petroleum jelly to the o-ring to ensure a good seal.
  11. Refit the pump lid turning it clockwise. Do not overtighten. Only hand tight.
  12. Remove the skimmer basket plug and replace the skimmer basket.
  13. Remove the return jet plugs.
  14. Turn the multivalve position back to FILTER.
  15. Open the AIR RELIEF valve on the main filter if you have one.
  16. Turn the pool pump back on.
  17. When only water is coming out of the air relief valve, then close it.
  18. The pool pump should now be primed and circulating the water throughout the system with now air.

Why Should You Keep Your Pool Skimmers Clean?

A pool skimmer is extremely important for the filtration of any swimming pool. It is the first stage of the filtration process in the pool system. Keeping your skimmers clean is half the battle won when you want a sparkling pool.

Remember cleaning out the skimmer baskets daily will keep them free of excess debris and the pool pump will be able to circulate the correct amount of water all the time resulting in a cleaner healthier pool.

There will be less strain on the pool pump, less debris moving through the main filter and less time will be spent adding unnecessary chemicals to your pool. Resulting in a cleaner pool.