Water features are still growing in popularity for many good reasons. A water feature, whether a pond or fountain, enhances any yard or garden. The sound of moving water soothes like nothing else. Moving water also attracts birds and other wildlife. The ecosystem that develops in a water garden provides the opportunity for children or anyone with the interest to study nature close-hand. The observation of the life cycle of fish, frogs and dragonflies is a great learning experience as well as entertaining. A pond provides other textures and dimensions adding interest to the garden. Waterlilies add not only visual interest but many are also very fragrant.
So you have decided that you want to enjoy some of the many benefits that a water garden offers. The first thing you should do whether you are planning to build the pond yourself or have it professionally built is to become acquainted with the various components that make up a water garden. If you choose these products carefully you should have a great pond experience.
Pond Liners
For a formal fountain with an intricate shape the best choice may be concrete. Concrete however is not usually the best choice for an ornamental pond, especially if owner-built. Concrete requires expertise to make a stable pond lining. Concrete also requires regular maintenance.
The average person who decides to build a pond will use either a plastic or rubber flexible liner or a preformed hard plastic liner. Preformed plastic liners are generally too small for a suitable pond. They also do not allow for you to design the shape of the pond and they have a short life span. Plastic liners are available for a cost that is less than hard liners in most cases. Plastic liners are a good choice for large ponds (1/4 acre or larger) as this material is light weight and can be made in single sheets to cover ponds up to approximately an acre in size.
Rubber pond liners are generally the best choice for most ponds. This material is very flexible (even in cold weather), puncture resistant, UV resistant, easy to install, and will last a lifetime.
Although plastic and rubber liners are very puncture resistant, one should install a material under the liner to protect the liner from sharp rocks and roots. Sand can be used although it is difficult to adhere to the sides of the excavation and it tends to move with ground water. Old synthetic carpet can be used if carefully inspected for pins and tacks. The best material to use is a commercial material available simply called pond liner underlayment. This looks like a thick felt. This material does not decompose in the ground.
Pumps
Most ponds will require a pump. A pump allows you to move water from one place to another, such as from the pond to a waterfall or through a fountain. This action aerates the water and improves the water quality.
A pump is also necessary to operate a filter that will further clean the pond. There are several things to consider when selecting a pump for your water garden. Some pumps are submersible which simply means that they are submerged in the pond water. Other pumps are external and are placed outside the pond. If your pond is small to medium then you will most likely use a submersible pump. Submersible pumps come in many sizes and generally last from two to eight years. These pumps are of two basic types: magnetic drive and direct drive. A direct drive pump has a shaft that penetrates the pump housing through some type of seal. This is the weakest part of the pump and the source of most failures. Since the shaft is in direct contact with the motor you get a pump that is capable of pumping at high head pressure. This means the pump can raise the water to high levels but costs more to operate than a magnetic drive pump. A magnetic drive pump uses a magnetic shaft to drive an impeller. The shaft does not penetrate the motor housing but spins floating on magnetic waves. Because of this, the pump should last longer than a direct drive submersible pump but has a lower head. This means that the pump will cost less to operate but will not pump water as high as a direct drive pump.
External Pumps
External pumps are usually more efficient for moving large volumes of water and are most often used in medium to large ponds. A good external pump should last six to twelve years. External pumps designed for water gardens have a similar appearance to swimming pool or spa pumps but are very different. Because of the types of filters used in swimming pool applications the pump must have a high head. This type of pump must work much harder than a water garden pump, therefore it will not last as long and it costs much more to operate. They also make a fair amount of noise. External pumps designed for water gardens are very economical to operate using about 1/3 the power consumption of a swimming pool pump. They are relatively quiet and should not be heard over the sound of the water.
Filters
Several types of filters are available for water gardens. There are chemical filters that use some type of chemical (carbon is one) to remove toxins from the water. These are not the most common filters in a pond. There are also mechanical filters that physically remove particles from the water. A mechanical filter may use paper cartridges, reticulated foam, fiber mats, brushes or other forms. The design of the filter allows for particles to be trapped in the filter media requiring frequent rinsing of the media to remove the trapped particles. This type of filter will remove the suspended particles in the pond water but requires frequent cleaning to be effective.
Biological Filters
Biological filtration does most of the work in improving the water quality in a pond. A biological filter may take many forms but basically it is a container that holds a filter media that the pond water flows into or is pumped into and then back into the pond. Several types of bacteria then live on this media and do the work of cleaning the pond water by converting one chemical into another. This makes the water safe for fish and helps reduce the amount of algae. Some of the more common types of filter media are plastic shapes, fiber mats, ribbons, and synthetic or natural gravels. The major differences are reflected in the efficiency of the material, how often it requires cleaning, and the ease of cleaning. A biological filter can be in the pond or out of the pond. Most biological filters will also provide some mechanical filtration as well. When installed in a pond the filter must be small enough to be easily removed for cleaning purposes therefore an in-pond filter is only suitable for small to medium ponds. Depending on its type, an external biological filter will be installed in the ground next to the pond, inline with the plumbing leading back to discharge into the pond, or behind a waterfall. A filter that is installed behind a waterfall is most often a gravity type filter, meaning that the water is pumped into the filter and it then flows back into the pond by gravity. This type of filter requires very little cleaning.
A pressurized filter and its plumbing can be installed at any level since the water in it is under pressure. This type of filter most often looks like a swimming pool sand filter but is very different. The inside of the filter is different as well as the filter media. The filter material most often used in these filters is a plastic media. Sand filters are for very clean water and are not a good choice for ponds.
When using an external biological filter it is recommended that you also use a prefilter, which will serve as a mechanical filter to remove the larger solids. This is the filter that will be cleaned most often so you should look for one that is easy to clean. A skimmer is the easiest prefilter to clean and is preferred for most applications.
Skimmers
Skimmers can be installed on most ponds. Some skimmers can mount inside the pond but most are installed outside the pond with the water entering the skimmer through a floating weir. Skimmers have some type of basket or net for catching floating debris. They may also have a fiber mat or other media to provide mechanical filtration as well. There can also be some mechanical filter media to provide enough biological filtration for smaller pond sizes. A pump will sit inside the skimmer and pump the water to a waterfall or another filter. An external pump could also be hooked up to the skimmer pulling water from the skimmer and then on to the pond. A well-designed skimmer will allow you to remove the basket and or mechanical filter media without you even getting your hands wet.
UV Sterilizers
Ultraviolet lights are considered another type of filter. This device uses a germicidal lamp to kill algae, germs, and virus. It can be inside another filter or skimmer or as a stand-alone unit that is connected to the plumbing in your water garden. There are many sizes available. They are rated in lamp wattage. When used as a clarifier you can use a lower wattage unit. In this application the UV unit will provide relatively clear water. When sized as a sterilizer you should be able to maintain crystal clear water as well as reduce the number of parasites and harmful bacteria in the pond. Even though a UV can sterilize your pond water as it flows through it, it cannot and should not sterilize the pond. Not all UV’s are created equal. Manufacturers may state that a particular size UV is suited for a specific pond size. You need to know if they are sizing the unit for clarification (in which case you will need about 2/3 of the pond surface covered with plants as well as the proper number of underwater plants) or they may mean for sterilization. Also some UV lamps are more efficient than others. You will also want to look for a design that does not restrict the water flow from your pump.
The Perfect Pond
To sum it up, you can have an in-pond filter with a submersible pump attached to it in a small to medium pond as your only filtration. This set up will work but the filter is in sight in the pond. It also takes more effort to clean, as the filter must first be removed from the pond. A better option for this size pond would be to install a skimmer that also has filter media to provide mechanical and biological filtration. You would have a choice of a submersible or an external pump for this set up.
The best option for a medium to large pond would be to have a skimmer installed to provide mechanical filtration since cleaning the media in a good skimmer is very quick and easy. Also you should have a biological filter sized for your pond. The best choice would be a pressurized filter with super efficient plastic biomedia installed. This filter allows cleaning by simply operating a valve to backwash the filter. However this comes at a price. If your budget is tight then I recommend using a skimmer with a waterfall tank biological filter. This type of filter would usually be installed behind a waterfall and only requires cleaning about once a year if a open media like a bio-ribbon is used. A UV is also recommended installed either in the skimmer or inline. The UV will insure that the water is clear year round. This setup will provide the least amount of work and the best water quality so that you can spend more time enjoying your pond.
Choosing pond supplies does not have to be complicated. However, in order to do it right, it will take a little research or the advice of a trustworthy expert.