Is it essential to have a pond pump
No a pump is not essential. If you just have a wildlife pond or just one or two fish with plenty of plants growing, in and around the margins of the pond, you can have a crystal clear garden pond without using a pump. However most people want an ornamental pond with numerous fish, a waterfall or fountain, or perhaps there is a limited number of plants and the water is green or cloudy, in these instances a good pond pump becomes essential. Apart from running a water feature or filter moving the water around helps the fish by improving the oxygen concentration in hot weather Choosing a pond pump
The first decision to make is to decide what job the pump is needed for: - Filtration
- Supplying a waterfall or stream
- Supplying a water feature or water spitter
- Fountain
- a combination of any of these
Pumps with a flow rate of up to about 2000 litres per hour tend to be multipurpose and for small ponds they do a fair job, no matter what purpose they are needed. On the down side the smaller and cheaper pumps tend to have a sponge filter which gets blocked easily and needs squeezing out every few weeks to maintain a decent flow rate. The sponge can be a good thing for a small fountain as it stops the fountain nozzles getting clogged, for powering a filter it's a bit of a nuisance. Don't ask a small pump to do too much by running a fountain and say a filter at the same time, it will end up doing neither job very well. A better option is to use the pump to supply a filter, and then using the water being discharged from the filter to run a stream or small waterfall. If you do want a pump to run a fountain and a filter either buy two small pumps or buy a larger pump with a bigger flow that can be divided between the two jobs Larger pumps, generally those with a flow over 2000 litre per hour, usually have no sponge filter, instead they can handle solid particles up to about 8mm diameter without becoming clogged, and the plastic cage round them stops larger particles entering the pump. The only maintenance these need is a quick brush to clean the outer case/cage, or you can fire a high pressure hose at it to get it clean. A good tip is to raise your pump off the floor of the pond by standing it on bricks or something similar to keep it from getting blocked with fallen leaves etc. The bigger pumps tend to be good at either moving a lot of water at low pressure quickly, ideal for supplying a filter, or the high pressure pumps are good at shooting water vertically upwards to power a fountain or spitter. These larger pumps can be used for a combination of fountain or filter/waterfall Choosing a filter pump
The design of specialised filter pumps means they can handle most solids without the impellor becoming blocked, for this reason they tend to cost more than fountain type pumps but they operate at lower pressure, are more efficient and therefore cost less to run. The water from a filter can be returned to the pond via a hose, or for extra appeal, let it cascade down a stream or waterfall What size pump to choose
If you have a wildlife pond, or a garden pond for goldfish the pump needs to circulate the water every 2 - 3 hours. So calculate the volume of the pond and if, for example, your pond holds 1000 litres you should choose a pump with a flow rate of 500 litres per hour or better. If you are keeping Koi the water quality and oxygen levels need to be better than necessary for the hardier goldfish so the ponds volume needs to be moved about once per hour, so a 2000 litre pond would need a pump which moves 2000 litres of water per hour. One more thing to take into account; the manufacturer always states the maximum flow rate of a pump, but this is at ground level, the higher the water has to be pumped before it exits the hose (called the head) the less the pumping capacity. A filter which is quite a lot higher than ground level will need a much bigger pump to supply the correct amount of water to the filter in order to keep the pond healthy, so take this into account when choosing how big a pump you need - more power is always better than less, especially for koi keepers. Most pumps have a chart on the side of the box which states the water flow at different heights (if you require this information and it is not provided in the online description give us a ring on 01302 783434 so we can find it for you). Choosing a pump for a waterfall or stream
A filter pump can double up as a good way of supplying a waterfall or stream because the filtered water can be returned to the pond via these water features without any detriment, but choose a pump powerful enough at the delivery height (the top of the waterfall) to give a decent flow of water. For every 25mm width of stream/waterfall you will need a pump that can deliver 250 litres of water per hour at the top of the waterfall, otherwise you can end up with a trickle that just doesn't look attractive. Example: a stream 250mm wide needs a pump that delivers 2500 litre per hour at the top of the fall. The hose width also affects the water flow, a wider hose reduces the pressure and allows a more efficient delivery of water and a better flow, narrow hoses restrict the flow so given a choice always choose the widest hose which is practical Choosing a pump for fountain
A pump for a fountain needs to be high pressure to shoot the water vertically upwards and therefore they are less efficient and use more power than a filter pump. Small pumps use a sponge which stops the fountain attachment becoming blocked. Larger pumps use a cage to prevent particles entering that would block the fountain attachments, they become blocked less frequently than the sponge type pumps but still the cage will need a brush now and again to keep it clean. Remember to keep the pump off the bottom of the pond to reduce the amount of debris trying to enter the pump. You can also choose a fountain attachments like a foaming jet which has no small holes to become blocked. The flow from powerful pumps can be used to supply a filter as well as a fountain |
