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Allotment Articles1.
Allotment Articles 2.
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Choosing A Pump
There are many things to consider before buying a pump. You have to have a firm idea of what you want the pump to do immediately and also what you might want it to do in the near future. It is no good buying a small pump for a fountain if next year you are going to add a biological filter and waterfall.
Pumps come in a wide range of sizes from tiny ones costing about £20 that are capable of producing a 12 inch, or 30 cm high fountain up to giant ones costing hundreds of pounds able to produce massive waterfalls. To put it simply the more you want the pump to do the bigger pump you will need and it's no good buying a pump because it is cheap. You have to ask yourself why it is cheap; it may be because it is very small, or because it is a discontinued model. Either way you may be disappointed.
Some pumps are more economical to run than others, such as central heating pumps, but these can be difficult to install, as they need priming to run again after every time they are turned off. If safety is a concern then low voltage pumps are available, but again these can be more difficult to install as the transformer is not usually waterproof, so a special chamber has to be built to house it near the pond. However, with R.C.D.’s or earth leakage trip switches fitted to most houses these days, it is usually considered safe to use mains voltage pumps and these are by far the most popular types sold.
When comparing pumps the manufactures usually help by numbering their models with their performance in gallons at a standard 3 foot or 1 meter head, or sometimes now we are going metric in litres per hour. Hence a model 300 will pump 300 gallons per hour and a model 2000 will, unless it is a very expensive model, pump 2000 litres that is about 450 gallons per hour. Some simple guidelines about choosing a pump are as follows: Up to 200 GPH, or 900 liters the pump should be considered for fountains only. 200 to 500 GPH can be used for a fountain and waterfall depending upon the height of the waterfall and the construction. Models above 500 GPH, or 2250 liters per hour can be used for high waterfalls or large filtration systems.
Running costs of pumps increase with the size of the model concerned but very roughly in continuous use it is about 3 ½ pence per watt per week. So a 70-watt model will, if run for 24 hours a day, cost about £2.40 a week to run. When you consider the rest of the money you have spent on your hobby of fish keeping, this cost is a small price to pay for the pleasures that a pump can bring and the life that it can create in your garden.
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