Fishing is central to the livelihood and food security of approximately 200 million people worldwide, while one in five people depends on fish as their primary source of protein. But according to an estimate by the UN’s Food and Agriculture Organization (FAO), over 80 percent of the world’s fish species are either fully or over exploited, or depleted.
The alternative to overfishing has been the development of “fish farms” – enclosed areas, usually set up near water sources and coasts, where fish are raised in a controlled environment. They have been around for years, enabling growers to set up controlled conditions that can ensure a specific yield of fish.
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But these farms also have limitations. While they enhance the conservation of fish in the sea, fish farms are often considered environmental hazards because of the waste generated by the fish, such as nitrogen, which is then dumped into the sea.
Israeli company GFA says it offers a solution to the geographical and environmental constraints of fish farms: They created a way to run fish farms anywhere, even in extreme conditions like the desert, with minimal damage to the environment.
Special biological filters
Based on the work of Israeli scientist Dr. Yossi Tal and Hebrew University professor Jaap van Rijn – inventor of the system – GFA has developed an on-land environment where fish can be raised, without having to exchange water or treat it chemically.
“We call this a zero-discharge system,” GFA Advanced Systems CEO Dotan Bar-Noy has said. “We use biological filters and specially developed bacteria to treat the water the fish are growing in, without wasting anything. The system can be set up to raise salt-water fish anywhere in the world – even in the desert, thousands of miles from the ocean,” he said.
Prior to the GFA solution, purification systems were based on electrical treatment systems, which are expensive to install and run, and not all that effective, says Bar-Noy. “Even when they work, the electrical purification systems are too expensive, and fish produced with those systems will cost far more than fish from the sea.”
Tanks using the GFA system are filled with water and fish and then the GFA microbes are added. These microbes treat the nitrogen and organic waste byproducts of fish production right in the tank. No water is discharged at all; in fact the only fluid exchange is the addition of water to replenish that which is lost through evaporation.
The company even alleges that fish grown in tanks purified with their product taste better because of the clean water they grow in.
GFA’s system has already been set up in several locations in Israel and the company runs an additional purification facility in New York, which has been operating since 2009. The New York facility produces about 100 tons of fish last yearmostly salt-water fish like sea bream, bass and tilapia.
The resulting system allows for high-capacity aquaculture, with as much as 100 kg of fish per cubic meter of water. In addition, due to the ability to grow fish in any environment, including in large cities, fish can be brought to markets the same day they’re harvested. This enables farmers to reduce transportation time and costs.
The company was formed in 2008, but the technology behind it has been under development for the past 20 years. “While the ideas were there for awhile, the only viable purification techniques were based on electrical devices. It was only with the rise of biotechnology techniques that we were able to develop the bacteria that enable us to do the purification cheaply,” Bar-Noy explains.
Photo by Bytemarks
The bacteria used by GFA’s system are cheap and easy to produce, so any initial costs for purchasing a system are more than offset by the savings realized in not having to clean tanks.