FORT PIERCE, Fla. - Pompano and tilapia are two fish that would never meet in the wild.

But the saltwater and freshwater cousins are chasing after each other in landlocked tanks as scientists try to find new ways of meeting the worlds' growing appetite for seafood by raising fish outside the ocean.

"All reports indicate that our wild resources have hit a plateau. There's just not enough fish in the ocean," said industry analyst Howard Johnson. "So aquaculture provides a big opportunity."

The average American ate nearly 16 pounds of seafood in 2002, up 7 percent from the year before, according to the National Marine Fisheries Service. Johnson predicts that by 2020, an additional 1.1 billion pounds of seafood will be needed annually to meet the growing demand.

Researchers at the Harbor Branch Oceanographic Institute believe new technology in the aquaculture industry promises to help create that needed supply.

In addition to pompano, a species with tight controls on its catch, researchers are working with flounder and black sea bass in less-salty water - building off the species' natural tendencies to wander away from their traditionally salty habitats.

The technology would allow the marine fish business to move away from the expensive coastline, giving more farmers across the country a chance to expand or convert their farms.

"You go to a state like Kansas or Missouri and the idea of having fresh fish and shrimp on the dinner table every night is very appealing to them but that option isn't always available," said Kenneth Riley, Harbor Branch's director of aquaculture education. "This is definitely giving you more options than the beef and chicken diet."

The switch from saltwater to freshwater is only one way Harbor Branch researchers are working to boost production. Along with the U.S. Department of Agriculture, they're developing ways to encourage fish that might spawn once or twice a year in the wild to become more productive.

Flounder, for example, spawn in the winter, but tanks in greenhouses with controlled temperatures and lighting can trick the fish into speeding up their natural instincts.

"The fish will think it's winter in the middle of a Florida summer," Riley said.

Other techniques to boost production include breeding fish within a species that have shown to be faster-growing, more nutritious or more disease-resistant.

"In the chicken industry, they grow them faster, fatter and cheaper. And that's what eventually will happen in aquaculture," Johnson said.