Yellow tang aquarium fish swim in a tank at a store in Aiea, Hawaii. The fishery off the Big Island is the focus of a fight over whether it's appropriate to remove fish from reefs for aquariums.

HONOLULU — The waters off Hawaii's largest island are home to a half-million brightly colored tropical fish that are scooped up into nets each year and flown across the globe into aquariums from Berlin to Boston.

Scientists say the aquarium fishery off the Big Island is among the best managed in the world, but it has nevertheless become the focus of a fight over whether it's ever appropriate to remove fish from reefs for people to look at and enjoy.

Activists have launched a campaign to shut down the buying and selling of fish for aquariums, saying the practice from Hawaii to the Philippines is destroying coral reefs.

“In this day and age, where the ocean faces a crisis ... there's absolutely no justification for a fishery for hobby,” said Mike Long of Seattle-based Sea Shepherd Conservation Society, which is spearheading the campaign.

A coalition of fishermen, state regulators and even local environmentalists say the group should focus its attention elsewhere, noting comprehensive aquarium fishery regulations and scientific research that shows fish stocks there are rebounding.

“We don't have a problem here anymore,” said Tina Owens of the environmental group Lost Fish Coalition.

Scientists estimate the aquarium trade removes about 30 million fish from reefs around the world. Hawaii accounts for less than 2 percent, while the vast majority comes from Indonesia and the Philippines.

Some fishermen in these countries capture fish by pumping cyanide into the water to make fish sluggish and easier to catch. The chemical may also harm nearby marine life, as well as shorten the captured fish's life span.The Philippines has long prohibited cyanide fishing and in April banned certain types of fishing gear that destroy coral reefs and other marine habitat, said Asis Perez, director of the government's Bureau of Fisheries and Aquatic Resources.Hawaii collectors use nets to capture fish. Local collectors may sell one yellow tang — the most commonly caught species on the Big Island's west coast — for about $3 or $4. With middlemen adding costs to store and ship them, the fish may retail for anywhere between $30 and $60.

File-This undated file video frame grab shows a scuba diver swimming toward activist Rene Umberger moments before ripping her air supply regulator out of her mouth near Kona, Hawaii, from a video released by Umberger. The underwater scuffle is highlighting a long-running dispute pitting environmentalists who want to shut down the industry in Hawaii and collectors who gather aquarium fish and sell them for a living.