For most people it is hard to find a cold water fish as desirable as koi, be it the variety of patterns, colours or just their sheer size and presence. For some people they are the reason to build an ecosystem pond in the first place. However, they require adequate living space. Koi often grow up to 2 to 3ft in length and come sometimes exceed 4ft (1.2m) and so require a sizeable pond to be able to house them, we recommend a pond no smaller than one of our 3m x 2m ecosystem ponds. It is important not to get carried away and over-stock your pond as you have to allow the fish space to grow and swim.
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