A pond skimmer is used to remove floating debris from the water surface of your fish pond.
They can be fixed at the edge of your pond at surface level or float free on the surface of your pond.
Why would you need a pond skimmer.
The trouble with garden ponds is they are normally located outdoors.
Being outside they have a tendency to collect debris on the water surface.
There are many ways debris can end up in your pond, leaves and sticks falling from trees is a major problem if you have lots of trees nearby.
Grass, mulch and all sorts of bits and pieces can be blown into your ponds water from all around your garden, the plants that grow in your pond can also shred leaves and petals.
If you do nothing to remove all this debris it will eventually get waterlogged and sink to the bottom of your pond where it will start decaying, this will affect the water quality and could lead to high levels of ammonia which is toxic to fish.
A garden pond is a closed system so anything that enters your pond has nowhere to go unlike a natural pond that has rivers running into them which constantly moves the water along with the debris, renewing the pond with fresh water as it does so.
A pond skimmer is usually installed at the waters surface, it’s job is to suck in all the floating debris like leaves and sticks from the surface of the water before it sinks to the bottom of the pond.
The debris is captured in a basket or filter and will need to be cleaned out, how often it needs to be cleaned will depend on how much debris finds its way into the pond and to the skimmer.
You could use a net to scoop out all the fallen leaves, but you would have to do this on a daily basis, a skimmer gives peace of mind, it still needs cleaning but not daily and its quicker.
Where to place a skimmer.
A pond skimmer can be located anywhere that the design of your pond allows, as long as there is a flow of water that encourages the debris to enter the skimmer you should be fine, if possible place it opposite the water return or waterfall.
A submersible pump is usually placed in the skimmer box although you can use an external pump by putting the pump intake inside the skimmer box.
With the pump running the water is naturally drawn into the skimmer box bringing with it all the floating debris.
Inside the skimmer box you will have a filter basket that catches all the debris or foam which also catches the debris.
Once the water has passed through the skimmer it can be directed to a filter system, a waterfall or directed back into the pond.
You need to watch the water level of your pond, if it drops to low the water won’t be sucked into the skimmer and if it’s running your filter system this could cause all sorts of problems with water quality and the ponds ecosystem.
Which pond skimmer should you choose.
There are lots of different skimmers from many manufactures on the market, which one you choose depends on a few factors.
If you have lots of trees near to your pond the amount of leaves that could fall into the water could soon clog up a skimmer, especially in the autumn.
If this is the case you should choose a skimmer that’s easy to access and empty.
The quality of the skimmer plays a part, a low quality pond skimmer will break down in time as the low quality of plastic used gets brittle, its not just the box of the skimmer that breaks down, the plastic filter basket can also be affected.
A box skimmer is fitted at the edge of your pond and is integrated into your ponds liner, these are easy to clean as the skimmer box is easy to get too.
You can also buy a floating skimmer that floats on the surface of the water, they have a pump fitted inside them so no external pump is needed.
There’s also an in-pond skimmer, these sit on the bottom of your pond.
A riser pipe has a skimmer head that floats on the surface of the water and will self adjust depending on the water level.
They use a hose from the inlet of a pond pump to draw the water into the skimmer head.
These are good choice as they don’t need to be fitted into the liner of the pond as would a box skimmer, if they do get damaged they are easy to replace, just take it out of the water and replace with a new one.
The downside is they are a little harder to clean out as they are harder to get too.
When choosing which skimmer to buy you should consider the pump, to make sure the pond skimmer can keep up with the pump you need to choose a skimmer that has the same or similar flow rate of the pump you are going to use.
If you have fish in your pond you don’t want them disappearing into the skimmer so look for a skimmer with a floating door, this will prevent fish from getting into the pond skimmer keeping them safe.