FREEPORT – The owner of a popular Chinese restaurant plans to appeal the state’s denial of a permit that would allow him to reclaim the 10 exotic fish seized last month by armed wardens from their tank in the restaurant lobby.

Cuong Ly was notified last week that the Department of Inland Fisheries and Wildlife had rejected his application for an importation permit for his 12- to 14-inch pet koi and that he had 30 days in which to appeal the decision to a three-member review board.

A pet shop in Portsmouth, N.H., has custody of the goldfishlike ornamental carp pending the outcome of Ly’s battle to get them back.

The Vietnamese-born owner of the China Rose restaurant also faces a Sept. 19 court date in West Bath on a criminal summons for importing freshwater fish without a permit, which is punishable by a fine of up to $10,000.

Maine has some of the nation’s strictest laws to prevent native freshwater fisheries from being harmed by invasive species such as carp. Fish and game officials fear that the koi that Ly kept in his restaurant could someday wind up in streams or ponds, where they would compete with native fish.

To get his fish back, Ly must prove to the review board that the fish are free of disease and that they pose no threat to native fish populations.

“He must also show that there is no chance of them being put into Maine’s waters,” said Mark Latti, spokesman for the Maine Warden Service.

“Anyone has to do this before they get a permit,” he said. “This isn’t unusual. Species like this, if placed into waters in Maine, out-compete native species like Atlantic salmon and brook trout.”

“Carp, especially, are a very serious threat if released into the wild. They are bottom feeders and eat by scooping dirt up from the bottom. They degrade water quality. The water becomes murky, and property values can decrease,” Latti added.

Ly said the fish were like family members and had been on display since he opened the restaurant nearly 15 years ago. He credited them with bringing good luck to the business.

Latti said the fish were illegal in Maine well before Ly placed them in the tank.