Responsible for the lives of millions of fish

"I am passionate about supporting both farms that are facing difficulties or those looking to expand because, at the end of the day, I really love fish, I love aquaculture, and I want the industry to succeed. When you have the responsibility for millions of lives. It can be super exciting and gratifying."

We got to visit Matt at AquaGen Profunda, where Artec Aqua provides the engineering expertise, machinery, and tank systems.

A suggested subject brought him across the world

Matt completed his bachelor's degree at the University of California, Davis, a big agricultural school in the U.S. before he completed a master’s degree in Aquaculture at NMBU. Both the academic side of his studies and the social part was incredible, according to Matt. 

"There was always something interesting going on at NMBU, whether it was intellectually stimulating, fitness, environment, or exercise. I think the community is so welcoming for internationals. The international aspect of NMBU really lends itself to exploring new ways of thinking and opening yourself up to perspectives that are varied and different."

"I can't speak highly enough of my time at NMBU, whether it's from the academic and the preparational side of things, or whether it's from the social, cultural experience side of things. It was a great time. One of the best decisions I ever made, I think."

The interest in fish brough Matt all the way to Sri Lanka, where he worked on a tilapia farm, designing a feed mill and rehabbing their ponds. Then his job took him to Iceland, where he worked with one of Artec Aqua’s facilities. Now he’s based in Ålesund, Norway.

Land-based farms offer more control over biosecurity

The difference between land-based and sea-based fish farms boils down to the level of control the business wants. For sea-based fish farms, there are three different kinds of farms. There’s closed, semi-closed and open. Sea cages are more intertwined with nature and the environment they in.

• On land-based farms, you have a very similar structure with varying levels of control.

  1. 1. Pond culture, the kind of farming that they're doing for shrimp in Southeast Asia, tilapia in South America, most carp species all over the world, and catfish in the U.S.
  2. 2. Flow-through is when you use the water only once, it goes into your production unit, past all the fish and then out.
  3. 3. Hybrid flow-through or reuse is where you are recycling the water, reusing the water a little bit more. For this, you need to think about if you need some extra oxygenation, degassing, or filtration. It gets more intensive, but you have more control.
  4. 4. RAS varies upon the degrees of reuse. RAS in general works in a way where you are at such a low water exchange level that you need some sort of nitrogen filtration. For the land-based side of things, the system you use depends on your water availability.

"The fun thing about land-based fish farms is that you have so much control. Land-based farms can take warm water fish and run production in a cold environment, and vice-versa. Different from sea-based, land-based farms can control the temperature, the oxygen in the water and particles."

"You have the control of your biosecurity because you can do UV treatments or ozone treatments to kill off any pathogens that can harm the fish. In a lot of ways, it’s more environmentally friendly because you control what enters and leaves the farm."

Fish health at the forefront of the industry

Fish health is incredibly important, both for the fish and consumers. The fish will let you know, explains Matt, and keeping the fish healthy is good for the farmer. 

"If you understand fish behaviour, you’ll be able to spot any strange anomalies in the fish. But, at the end of the day, it starts with the water. It’s where their oxygen comes from, and where their nitrogen goes when they excrete. There’s even been some research on whether fish should get ‘exercise’ in the tanks. A good tank environment is making sure that it’s good water quality, a good source of light and a way to collect mortalities. You want to inspect those because that's part of maintaining good health. It’s knowing why fish might die."

Salmon with earthy flavour?

As Matt shows us around the farm, he explains that a strange thing happened when farmers moved the production on-land. The same compound that gives off petrichor actually developed in the tank. It’s not harmful to the fish, but when the fish was dissected, they realised the filet tasted like dirt. 

"It’s incredibly pungent. That’s the odd thing about working with land-based farms. It’s still such a new industry on a mass scale, that we’re discovering new things all the time and figuring out how to manoeuvre the challenges that do occur."

A circular economy in the aquaculture industry

Making the aquaculture industry as sustainable as possible is an important part of the industry’s challenges today. How can aquaculture be more sustainable, and is the industry equipped to handle the challenges of climate change in the future?

"Protein production from fish is the lowest carbon footprint of any animal protein. It doesn’t mean we can’t do it better. We need to do something with our effluent, because if you look at what agriculture needs, it’s nitrogen and phosphates, and fish effluent is rich with those. We must start generating a circular economy."

He explains further that there are businesses doing biogas generation and running power plants from it. The fish’s excrement is also used in agriculture, where farmers mix it into the fertiliser and spread it on the fields. Because the industry is so young, it’s possible to come up with new ideas. 

"Sometimes the rules and regulations need to catch up. I think climate change wise; we're implementing all the same things that everybody else is. We're the best animal protein source for climate change. In terms of sustainability, we have some work to do, especially on the feed side, but on the other side of it we essentially reuse most things."

• Are you interested in learning more about a master's degree in Aquaculture at NMBU? Read more about the course here.