A Chicago chef faces charges that he attempted to violate federal law by trying to buy 24 banned “dragon fish” — which can fetch thousands of dollars each — for his home aquarium, according to his lawyer and court records.

Sittipat “Ong” Satangmongkol recently opened the restaurant Thai Nang in West Town. He previously worked at Tsukiji Fish Market in West Town and Silom12 in Bucktown.

When he’s not cooking, Satangmongkol is an avid collector of exotic fish, said his attorney, Adam Sheppard. Dragon fish are also known as Asian arowanas and are highly endangered.

“He didn’t set out to violate the law. That said, he recognizes that the transaction was ‘fishy,’ ” Sheppard said, apologizing for the pun.

“Apparently there was an investigation of an overseas shipment of these fish and that led to this charge.”

Satangmongkol, 39, was charged earlier this month with a misdemeanor violation of the Endangered Species Act, which carries up to a year in jail. Sheppard said he negotiated with the government to reduce the charge from a felony to a misdemeanor.

He said his client intends to plead guilty and hopes to receive a sentence of probation. Federal authorities declined to comment on the case.

Sheppard said his client was a collector, not a seller.

Satangmongkol had visited an Internet forum called Monster Fish Keepers where he’d try to arrange purchases of other exotic species such as the Siamese tigerfish, according to his posts on that website. His last visit appears to have been in 2014.

Court records don’t tie the website to Satangmongkol’s alleged crime.

Satangmongkol was born and raised in Thailand and is in the United States legally, Sheppard said.

In August 2013, federal agents seized a shipment of live fish at O’Hare Airport, Sheppard said. He said Satangmongkol ordered the fish, some of which were legal.

But arowanas are illegal to purchase in the United States.

Arowanas are colorful — they can be red, green or gold or other colors — and grow to lengths of up to three feet. They have short whiskers and large, shiny scales.

“It’s actually one of my favorite types of fish,” said Chuck Knapp, vice president of conservation research at the Shedd Aquarium. “It’s gorgeous. They’re considered good fortune. People break into other people’s houses in Asia because they are so prized.”

Knapp, a world authority on iguanas, is a member of an international group that assesses endangered animal populations and offers recommendations on how to protect them.

Smuggling of endangered animals like arowanas is a major problem, Knapp said, but “rarely in these wildlife cases do people get severe time.”

“If people keep getting slapped on the wrist, there’s no fear of engaging in this type of behavior.”

In places like Singapore, wealthy people covet arowanas, and it’s considered one of the most expensive aquarium fish in the world. Some arowana owners in Asia have even paid for cosmetic surgery for their fish.

In the United States, an illegal arowana can cost $1,000 to $1,500 depending on its quality, Sheppard said.

Sometimes they can fetch even more, according to court records. In 2012, a man in Seattle sold two Asian arowanas to an undercover federal agent for $2,300 each. He was sentenced to probation, records show.

“We know that the more rare a species, the higher the price and the greater the demand,” Knapp said.

Currently, there’s a debate in the conservation community about whether to give the location of newly discovered species in academic publications, Knapp said. The worry is that smugglers can use that information to swoop in, capture the animals and sell them on the black market.

Earlier this year in Madagascar, he noted, about 12,000 critically endangered turtles were discovered in a home after they were poached from the wild.

“They were destined for the pet trade,” Knapp said. “It is a serious problem.”