AQUACULTURE Oxygen is a key ingredient in fish farming.
Why industrial gases are important in fish farming Fish farming, or aquaculture, is a sustainable way of increasing the supply of fish to a burgeoning world population. Industrial gases have an important part to play, according to Air Liquide.
F
ish is a nourishing, healthy food that is popular throughout the world. However, as the planet’s population grows, fish stocks in some oceans are dwindling. One way to address this shortage is fish farms. Popular in Europe, especially Nordic countries, aquaculture also occurs throughout Australia – from the tropical north to the more temperate climes of Tasmania. Like any commercial venture, there are many facets to make it a successful enterprise. When it comes to fish farming, an essential ingredient are various industrial
gases, which have many applications in aquaculture – from hatching the eggs through to when the final product is shipped for sale. Air Liquide is a gas specialist that has a lot of information and experience when it comes to fish farming. Its Tasmanian sales representative, Grant Stingel, works closely with the industry, not only as a supplier of gases, but also giving advice on how much, what type and how often a certain gas needs to be applied to the various production processes. The most prolific gas used in fish farming is oxygen. There are two
main reasons it’s needed. The most obvious is to sustain the life of the fish as they hatch and are grown. The other is a little more interesting. “During the production of farmed fish, one of the high cost inputs is the food,” said Stingel. “It can cost up to $2,000 a tonne or more depending on the species and feed type. Maintaining a stable level of oxygen in the tank increases the fishes’ metabolism, which in turn increases the conversion of food into fish mass. So the Feed Conversion Rate (FCR) reduces, meaning lower feed costs per kilogram of fish. “And if you’re talking tonnes of
fish, you’re talking tonnes of food per day. In the larger aquaculture systems, maintaining stable oxygen levels in the tanks will increase production. If you can increase the growth of the fish each day by adding oxygen, this reduces the time the fish are in the water, which in turn increases efficiencies within the whole production cycle. “Typically, modern land-based aquaculture farms use what is called a Recirculating Aquaculture System (RAS). This is essentially a water treatment plant to circulate and reuse the water. This plant uses pumps to push water through a series of
www.foodmag.com.au | August 2019 | Food&Beverage Industry News 23
