Test-tube Tilapia in Casa Grande
If the tests go as planned on a 5.5-acre plot south of Casa Grande, their tests literally could revolutionize fish farming worldwide, reports a member of the Casa Grande valley Newspapers Inc. "This is the first thing that will change fish farming in 50 years," Parsons said to TriValleyCentral.com of their idea.
Most of the product would be tilapia, a fast-growing, high-protein fish without a fishy taste that's ideal for fish sticks and many other dishes. That's important now because China had been supplying much of the U.S. market for tilapia before a cold winter destroyed much of that country's tilapia. And recent health concerns about hormones and other harmful materials in commercial fish foods, and about Chinese products in general, have put the safety of Chinese-grown tilapia into question anyway.
"(The U.S.) is spending $30 billion a year to bring fish into this country," Parsons said. Chile and Norway remain as major suppliers, but supplies are likely to be limited with China no longer in the mix. "We just have to prove that we can do it," Pierce said. "What we're doing here is a model farm to show what we can do." The fish would be raised in a series of underground tubes that should be incredibly efficient and self-sustaining. A worldwide patent for the process is in the works. There will be almost no water loss since the water shouldn't evaporate from the 20,000-gallon tubes buried a few feet in the ground.
Evaporation from above-ground ponds is nearly prohibitive in Arizona's desert climate, although there are some commercial fish- and shrimp-farming ponds in the state. Algae and water purity also are significant obstacles to raising fish in ponds, especially in Arizona. Water will be circulated so there's a gentle current in each tube. Each will be sealed off from the others, so a problem in one tube won't ruin the entire operation. A natural filtering system will keep the water pristine. Fish waste can be used as fertilizer for organic crops grown on the land over the tanks. Almost anything can be grown, as long as it can be hand-harvested so that heavy equipment doesn't have to be driven above the tanks.
The fish will be fed automatically, 24 hours a day. Tilapia are especially well-suited for the underground tubes since they are nocturnal. Fish will be harvested by sweeping a screen down the length of a tube. "We can adjust the screen and sweep for the size fish the customer wants," Pierce said. Each tube will be welded so there are no joints, and will be 3 inches thick, 220 feet long and 4 feet in circumference. Each tube would hold approximately one fish per gallon of water. The site would even have its own small fish hatchery, harvesting eggs from brood stock to grow its own fingerlings for stocking the tanks.
In addition to the 70 full-sized tubes, Parsons and Pierce are planning on 70 smaller test tubes, 2 feet in circumference and 70 feet long, in which to try their technology on other aquatic food: catfish, shrimp, salmon, halibut and more.
Picture text: Neal Parsons and partner Larry Pierce are working on the prototype at The Underground Fish Farm site
