| There is no doubt that the work horse of the Koi | | | | the external pump. The pump is placed after the |
| pond is the pump. Whether you have opted for a | | | | filtration system and so pumps clean water back |
| pump-fed or gravity-fed system, selecting the | | | | into the pond. This cuts down on the amount of |
| right pump is a critical step. The submersible pump | | | | cleaning required and being out of the water |
| is a common choice - widely available, relatively | | | | makes maintenance an easier chore. The biggest |
| inexpensive and very easy to install. They are | | | | drawback is that they need to be kept |
| placed either in the pond for a pump-fed system | | | | undercover in a dry space protected from the |
| or in the last chamber of the filtration system in | | | | elements. |
| the case of the gravity-fed system. | | | | When choosing your pump, make sure you get |
| The submersible pump for all its simplicity does | | | | one large enough to maintain the desired flow |
| have a number of disadvantages. The biggest | | | | rate and water pressure. Ideally you want to be |
| problem lies in the cleaning and maintenance. Since | | | | able to turn the whole pond volume over at least |
| the pump is either in the pond or the filtration | | | | every two hours. Also think about the power |
| system, cleaning requires removing the unit. This | | | | consumption. Today there new lower wattage |
| can be especially time consuming when the pump | | | | pumps coming on the market. These, while more |
| is in the pond. The submersible pump in the pond | | | | expensive to buy, will save in overall operating |
| can also become an obstacle on which your Koi | | | | costs. Just keep in mind these lower wattage |
| could injure themselves. In the filtration system | | | | pumps may not give you the power you need. |
| the pump takes up valuable space that could be | | | | As always, do your homework before you make |
| used for filtration media. | | | | your choice. A little due diligence up front will save |
| The option I like best for a gravity-fed pond is | | | | you time and headaches later on. |