Pond equipment

There three main components that are required to keep your water clear & your fish healthy.

These are pump, filtration unit & Ultraviolet clarifier. We will look at each of these below.

Pump

If you want to move water around your pond, whether it is for a fountain, a waterfall or a filter you will need a pump.

There are two basic types of pump for use in garden pond.

Fountain Pumps need to be stable and be able to operate efficiently for long periods. This type of pump has a prefilter of some description, this prevent debris from damaging the pump & clogging the fountain head. If you have a problem with the prefilter clogging, many manufacturers produce larger add on filter to increase the surface area and reduce the frequency of cleaning.

Sizing a fountain pump

Fountains should be a maximum of height of half you pool width, otherwise wind may blow the water out of your pond. Depending on the type of fountain head a 70cm high fountain requires 600 litres per hour. A 130cm high fountain will require 2000 litres per hour.

A typical fountain pump

Solids handling pumps These are ideal for powering waterfalls & filtration systems. They need to be able to operate for long periods of time without clogging, they also should be able to pass solids to the filter to enable them to be removed from the pond. As these power filtration systems that your fish rely on they should be reliable. Ideally they should also be energy efficient to reduce running costs as filtration units should run 24 hours a day .

Sizing a pump for a waterfall

For each 2.5cm of width a waterfall will require a minimum flow rate of 227 litres

(50 gallons) per hour. For example a 15cm (6") wide waterfall will require a flow rate of 1362 litres (300 gallons) per hour, at the top of the waterfall. Don’t forget that as the height of the pump outlet increases the output decreases. For example a 1400 litre per hour pump will only pump around 1050 litres per hour if it has to push water up 100cm.

Sizing a pump for a filtration system

Aquamax solids handling pump

Filtration unit

The purpose of a filter system is two fold

1. To remove waste material from the pond into a filter. This improves the clarity of the water and helps reduce the accumulation of debris in the pond.

2.Filters create a home for beneficial bacteria which break down poisonous waste produced by your fish into less harmful by products.. These bacteria occur naturally on all surfaces in the pond. An efficient filter contains media of very high surface area to create a habitat for very high concentrations of bacteria.

Filtration units fall into 2 distinct categories.

Pressurised filter

This are the newest type of filter on the market. They are smaller than most units and our mounted externally where they can be buried in the ground. Many are fitted with a UVC to help the clarity of the water. Due to the fact that the unit is pressurised the water coming out of the filter can be pumped up to a waterfall or other water feature.

Pressurised filters from Oase

Conventional filter

These are what most people think about when pond filter is mentioned. The unfiltered water is pumped in at the top often through a spray bar, this then passes through a combination of graded foam sheets and large surface area biological media. It then returns to the pond via a large diameter outlet. As the water returns to the pond via gravity the outlet must slope gradually towards the pond, or the filter may overflow. This type of filter has a built in overflow, so if the sponges become clogged water will still be circulated. Although it should be cleaned as soon as possible.

Conventional above ground filters from Oase

Ultraviolet clarifier

Ultraviolet clarifiers use Ultraviolet light to kill the single celled algae that cause the pond to go green. High powered versions of this unit were originally used to control disease in fish farms. The versions used by the hobbyist are much lower power and have very little effect on disease, but they will almost guarantee clear water.

The entire volume of your pond should pass through your UV approximately once every two hours.

Filtration

To effectively filter your pond the total volume of water should pass through the filter at least once every two hours. For example a 4540 litre (1000 gal) pond requires a pump capable of delivering at least 2270 litres (500 gal) per hour, plus additional flow for any other water features or equipment. Remember that the higher the outlet above the water surface, the less water the pump will be capable of delivering. Passing water through an Ultraviolet clarifier or magnetic treatment unit reduces the flow by 10-15%. The Oase Aquamax, ranges are well suited for filtration purposes as they can handle solids up to 8mm.

To convert litres to gallons divide by 4.54.