Few fish inspire greater devotion than koi. These large ornamental carp have now established a dedicated following in the West, matching that which they enjoy in their Japanese homeland. Koi were developed primarily for the beauty of their colors and patterning, when viewed from above. This led to great interest in breeding and showing koi varieties, and the most desirable individuals now change hands for huge sums of money. To appreciate these attractive pond fish fully, they must be clearly visible through the water; as a result, koi are most often kept in well-filtered water in a pond containing few or no plants.