Arizona aquaculturist designs ponds to irrigate row crops Fish farming in the Southern Arizona desert may seem like trying to sell Eskimo Pies to the Eskimos.

Tony Porti, University of Arizona's aquaculturist, admits it has not been a smooth learning curve.

"I've killed a lot of fish," admits a man who has successfully raised fish all over the world. The killing is over and he is seining in the dollars, integrating fish farming with conventional farming. That's probably the only way fish farming will work in Arizona.

Porti said there is a huge, untapped desert market for fresh fish.

Porti practices his academic expertise at the University of Arizona's Maricopa Agricultural Center (MAC) south of Phoenix where he learned how to design a desert fish farming system, manage the fish and how to market the final product.

"Fish farming is the fastest growing crop in the world," Porti says. However, it has not proven successful in Arizona until now. The many failures among private fish growers in Arizona, and Porti's own learning experience, have been daunting. But he says he now can grow fish profitably, and increase profitability on a farm by using water from the fish ponds to irrigate crops.

"I've managed several fish farms around the world," he says. He started in the Pacific Northwest raising trout and salmon. He has raised fish and shrimp on private farms in China and Indonesia, and he still consults with some of those companies. His Arizona experience, however, may have been his most difficult. But persistence has paid off.

The MAC fish farm now annually produces thousands of pounds of fish, selling to eager markets, and uses the pond water to grow UA crops. Porti wishes he had more fish to market.

Flexible ponds Porti's system is five flexible ponds. He raises tilapia, catfish, white amur and koi - some sold as food and others marketed for weed or insect control in urban ponds or irrigation canals and some as ornamentals.

"We can mix and match different species to different markets," Porti says. "That's important on these smaller operations."

His highest pond in the system, called Table Top, holds 4,000 triploid white amur or grass-eating carp averaging six pounds each. These amur are voracious grass eaters used in golf course ponds and desert irrigation canals to keep them weed free.

Table Top also holds 50,000 tilapia fingerlings, which are sold for both food and for algae and weed control. Amur sell for $1 to $1.30 per pound FOB, and the tilapia $1.30 to $1.65.

"We've designed reservoirs with catch basins - shallow areas where we can herd and harvest the fish," Porti notes. This is an important part of fish farming and one that saves on labor.

"We can do 8,000 pounds per hour," with only a few workers. he says of the fish roundup. The importance of design, both for growing and harvesting fish, can't be overestimated. "You design it wrong, and you're done."

The second pond is called Below Ground. It is smaller and used to grow the tilapia and amur to market size.

The third pond, called Pond One, is a half-mile from the first two ponds. It is particularly suited to growing large fish.

"It's our big cash cow," Porti says. "Right now we're producing catfish in it."

It raises catfish eight pounds or larger for the food market, Pond One produced 30,000 pounds of fish to sell last year at an average of $1.25 per pound. Porti also sells catfish from this pond to stock urban ponds for the Arizona Game and Fish Department's urban fishing program. This pond is long and wide and doesn't require an aerator because of the influx of Central Arizona Project and well water gushing through it.

Pond Two contains more white amur and is where koi are raised. About 50 percent of the koi are sold as ornamental fish. The rest are stocked in urban lakes for midge fly and mosquito control.

"Koi are the fish to have," Porti says. They are lucrative on the ornamental market, but Porti points out that the pond is small and not as well designed as the others. "We do make money with it, though."

The fourth pond, called Baby Frog, is a small pond that is now used to produce catfish fingerlings for the stocking of Pond One. It produces up to 30,000 pounds of fish annually.

Downstream, the last pond, called Frog Pond, a large reservoir where water from the other ponds ends up. It is mixed with well or CAP water and used to irrigate crops. "That water has been used four or five times," Porti says, so the pond is less productive. It now holds catfish, only because they escaped from other ponds.

Endangered species "Right now we're also looking at growing endangered species," he says. There is money in government programs to grow rare native fish for restocking purposes.

"Everything was designed around the crops and the wells," Porti says of the MAC system. Water flows through pipes from pond to pond, but it also can be introduced into any pond along the way if needed. The Gila River Indian tribe contributed to the construction five years ago, and the Gundle Co. donated hundreds of thousands of dollars worth of pond liners.

"We have a check and levy system," Porti points out. "Water can be pulled out or put in anywhere along the line." Adding water to a pond cuts aeration costs, because the fresh water is oxygenated.

The system saves the farm money in several ways. It allows the farm to store water for immediate use. That can be important in a system where ordering water from the irrigation district can take time. It also aids irrigation in pressurized irrigation systems like drip or sprinkler.

"There's a nitrogen cycle going on here," Porti adds, noting that fish water picks up waste along the way. That waste becomes nutrition for crops.

Porti says there are no restrictions on irrigating with the pond water, and MAC has used fish water on everything from cotton to vegetables, from wheat to Sudangrass. He cites studies that quantify crop production increases using fish pond water, but says the MAC crop managers report definite nutritional benefits.

"In terms of the organic crops, we're win-win," he notes, because fish wastewater is considered a nutritious substitute for expensive commercial nutrients.

Porti said good design and management are the keys to successful fish farming in the desert. Past fish farm attempts in Arizona have failed, largely because those were lacking. And he says that every farm that stood alone - and wasn't integrated with an adjacent crop farm - has failed.

"In the Southwest, to be successful, you have to be multiple use," he says. That's because the cost of the water is prohibitive if it isn't used several times. He cites the Cactus Lane farm in Litchfield Park as an example of a successful fish operation. It integrates fish farming with citrus.

"It's the only way to go," he says of an integrated fish/crop system like the one at MAC.

"If you want to do a food fish operation, you have to have capital and the design and the expertise," Porti says. Porti has developed a manual to help people get started.

"It's very exciting," he says of hisefforts to successfully introduce fish farming into the Desert Southwest, largely because there is a growing market. "There's more demand than supply."

Bright outlook Porti points out that declining yields from ocean fisheries as well as a growing human population-particularly among ethnic Americans such as Asians who eat large quantities of fish - bode well for future fish sales.

Porti developed his own markets over the years, beginning with farmers markets and street corners in Phoenix. Now he sells most of his food fish as "live tank" catch, which are transported to urban centers for processing.

Weed and insect control species of fish are also in demand. A proliferation of golf course lakes as well as reservoirs and irrigation canals increases the demand for tilapia and white amur. California, for example, legalized the use of sterile amur for weed control, and the market is booming.

"Fish farming is not a commodity crop," Porti says. Fish farmers must have aggressive marketing plans.

Porti is convinced the expertise is in place for successful fish farming in the desert Southwest where it has the potential to be a profit center for struggling conventional farming.