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The purpose of a Fish pond skimmer

One of the most forgotten about pieces of fish pond equipment has to be the fish pond skimmer yet it is also one piece of equipment that does a great deal for maintaining the water quality and aiding the fish pond filter in keeping the fish pond free from debris.

As the water surface of the fish pond is in direct contact with the air, foreign objects are always landing on it and in time these will slowly sink to the lower levels gradually decaying which in turn creates toxins in the water. Catching the air borne debris before it has the chance to enter the fish pond can prevent a lot of water quality issues over the year so the use of a fish pond skimmer pays for itself by working for you and reducing the amount of cleaning etc. that you would normally perform in the fish pond.

The most obvious debris that always falls onto any fish pond irrespective whether there are too many trees nearby has to be leaves in the autumn season as well as other rubbish that can be blown about, once these hit the water surface they are trapped and can be blown no further so it is up to you or your equipment to deal with the problem and I know which I would prefer to do the task.

What many people may not also realise is that there are also dust particles which are airborne, we have all seen soil blown about on a windy day in our gardens but some particles are too small to be seen by the naked eye but they are there. These will also land on the water surface which in turn increases the unwanted extras to our fish pond.

The designs of the fish pond skimmers are very basic and ideally the skimmer will be incorporated into the original design of the fish pond, to me it makes extra work having to build the fish pond just to then have to make a hole to fit the skimmer unit, best to add all the built in units initially. There are occasions when this just is not possible, you could have inherited the fish pond with a house move or the actual size of the fish pond may be too small but there are ways around adding a pond skimmer later that will be discussed further into this article.

Basically all that the fish pond skimmer does is to drag water into the top by means of a submersible water pump and as the water is passed through the unit any debris is trapped in a mesh or fine basket before the water is allowed back into the fish pond below the water surface. As mentioned above some skimmer units are built into the sides of the fish ponds and can be directly attached to the filtration systems, some are sole units in their own right but at the end of the day whichever unit you choose, they will aid the filtration system immensely. If you think about it the skimmer unit traps the debris and the baskets are always easy to access for cleaning, without a skimmer the same debris would be drawn into the filter meaning that the filter would need unclogging on a much more regular basis, this is nearly always a lot more time consuming than just emptying a basket.

You may now be asking the question “will this increase the running costs of the fish pond?”, yes it will slightly increase the running costs but unlike the running the fish pond filter for 24 hours a day during the spring, summer and autumn months, the fish pond skimmer does not need to be left powered up all of the time during the day. They only need to be run for a couple of times each day, each period of running time can be 2-3 hours and you will still see the results in the water quality and the debris that is trapped. The running costs can be added as for the skimmer to be effective they require a powerful pump to drag the debris through them in the first place, the average requirement of the pumps is at least 1500 gallons per hour, any less and they can only clean the immediate water around them, most fish keepers running this equipment will power them through a timer so that they are cost effective.

Always remember to keep the basket cleaned out or they will become clogged and this will greatly reduce the water flow through the pond skimmer.

So how much do these units cost? Surprisingly they are not that expensive, because they are so basic and simple in design, you can expect to pay as little as £60.00 per unit, not a bad price compared to other pieces of fish pond equipment that you require for a successful fish pond.

In more recent times the basic fish pond skimmers have been developed one stage further and it is now possible to obtain protein skimmers for the fish pond, these are becoming very popular with keepers of Koi fish ponds as they extract the dissolved organic compounds in the water as well as removing debris. Protein skimmers have been around for a few years and saltwater aquarium keepers are well used to using this equipment. A venturi creates a cascade of air bubbles in a chamber and as these rise the dissolved compounds such as proteins are attracted to the surface of the air bubbles, at the top of the chamber the air bubbles burst leaving the compounds in a collection chamber which can be removed for easy cleaning ready to use again. These units are sometimes referred to as “foam fractionaters” as the air bubbles create a foam, the more the amount of foam, the higher the level of dissolved compounds in the fish pond water.

Of course the protein skimmers do fetch higher prices but the clarity of the water is greatly improved and are well worth considering for Koi fish ponds. In my view I would not consider a protein skimmer for the smaller fish ponds, these can easily be skimmed by using the floating units and due to the small size of the fish pond, this in turn saves you having to incorporate the skimmer into your fish pond design, the floating units are small enough for small water volumes without taking up too much space on the water surface.

So to summarise, the fish pond skimmer removes the debris from the water surface, this in turn improves the water clarity and aids the fish pond filter making the filtration system much more efficient at its job therefore making the fish happier in the fish pond!

Surely this piece of equipment has to be a serious consideration on your shopping list of vital equipment for your fish pond!