For example, there are koi with light blue spots, ones with large red patches on their backs, or all-metallic gold. But the most winning fish often just boil down to these three varieties.

"The popular koi fish of today are actually ornamental varietals of domesticated carp," Hilstrom says. "Black carp originate from China and were first bred for red color mutations (noted around ...

The fish, a type of carp that can live for decades ... And then he spotted Bandit, the most special one of all — a white koi with a red band across its head — a species that is prized in ...