Contestants in fish-breeding competition prove to be carp of many colors.

Ernie DeTournillion is a man who takes his koi seriously.

Smitten by the urge several years ago to own some of the colorful carp, DeTournillion said Saturday, he sold his Long Beach home and bought another--this one with a swimming pool to hold the fish.

DeTournillion was one of 50 koi aficionados who showed up at Robert F. Peary Junior High School in Gardena Saturday for the Southern California Koi Club’s 20th annual koi competition.

Early Saturday morning, the breeders began arriving at the Normandie Avenue school from Northern and Southern California, Arizona and elsewhere, unloading their fancy carp and placing them in 68 portable tanks set up on the school grounds. Many of the show’s participants planned to stay overnight Saturday at the school in campers and trailers to safeguard their investments, whose value can reach $50,000, said show officials.

“This is where you get all the top guns in koi,” enthused Henry Nakamaru, whose father owns a koi shop in Gardena and exhibits his customers’ fish at the show. The Nakamarus brought 150 koi to the competition.

Since the early 70s, the school has been used by the club for its annual show. The club is the oldest koi group in the United States, said DeTournillion, who was videotaping Saturday’s judging.

This year the koi were judged by Yosaku Nakazawa and Takeshi Nakamura, breeders from Japan. More than 385 fish were entered, and from that stock, a grand champion and various other award winners will be chosen based on markings, size and color. The likely grand champion, officials said, was swimming in a tank with six other fish--with values ranging from $5,000 to $50,000.

Koi were first found around 400 BC in Iran. However, it wasn’t until the 1800s that people began breeding the fish to produce the wide array of colors found today.

All fish are photographed before the event so they don’t get mixed up. For DeTournillion, that is something that could easily happen in his own back yard; he has about 400 koi in his 35,000-gallon pool.

The show is open to the public today.