Build an aquaponic indoor farm – part 2 – design

This is a description of how we at Johannas Stadsodlingar (urban farms) and Concinnity together have built Johanna’s aquaponic pilot facility. We want to share how we did it and our thinking behind it. There is quite a lot to think about, so there will be several posts to cover most things. 

Part 1 – to start, prior knowledge
Part 2 – design (this post)
Part 3 – building log 

Our pilot facility consists of 290 m2 in an insulated building that was previously a cow barn for about 140 cows. The farm was built in the mid 80’s and was then very modern. We have taken a third of the space available in the farm building. The pilot plant uses three rooms: the large cultivation room, of approximately 220 m2, the seeding/sappling room 24 m2 and the ”packaging room” 20m2. The rest are side surfaces. 

In the pilot plant, we will grow leafy greens, spices and rainbow trout (yes, nitrification bacteria of course). 

The first design was based around IBC tanks and three cultivation troughs with 60 x 120 cm rafts. Outside the building there is an area reserved for the sump tank. The fish would be in IBC tanks. We thought of using a radial flow separator to remove the coarsest solid particles and a filter box for the finer particles. Just as described in The Aquaponic Farmer (see part 1).

One of the first designs of the Johannas aquaponic pilot facility (version 3).
2D drawing of one of the first designs (version 4).

In the floor plan above, you can see that we have already rethought using two cultivation troughs instead of three. A narrower trough for rafts from Meteor Systems and one with more traditional rafts from Royal Brinkman (120 x 60 cm). In the Meteor rafts, we use a smaller substrate plug with significantly less material consumption. In the Brinkman rafts we use plastic pots. We were not sure what would work best in the Swedish market, so we wanted to try both.

Since we have a concrete floor, we can not have part of the filter system below the throughs easily, so we investigated other options for the filters. We chose to have a small drum filter instead. At the same time, we began to wonder if the fish we had decided on, the rainbow, would not feel much better in round tanks. In addition, we realized that the sump tank would need proper protection, so we started planning a building over the tank. Eventually, that building became our engine room as well. It turned out that this was very good, but it was a lot of work.

To have better access to the room where we ship out vegetables, we turned the design so that the fish tanks are furthest from the packing room, while it also has less people moving around the fish tanks (the doors are not there) which reduces stress for the fish. The round fish tanks are also more volume efficient.

Round fish tanks and the design flipped 180 degrees (version 8).

In the final design (below) you can see that we added a ”pier” around the fish tanks. The tanks were so high that it would be better to be able to get up a little when working there, without having to stand on a footstool. At the same time, we wanted to get the filter tank (Moving Bed Bio Reactor, MBBR) up from the floor, as the water level in our design is determined by the outlet on the filter tank as well as avoid pipes on the floor so you do not have to step over them all the time. Despite a lot of thinking around this, some of it came out less than optimal. We have a higher water level than we think is good and it would be quite a lot of work to rebuild it to lower the level. But, as I said, the goal of a pilot plant is to learn.

Final design of the pilot facility (version 12).

The facility has 3782 growing places in the two troughs, approximately 3200 growing places (depending on which trays you use) in the tables in the sampling room. We can have a total of about 7000 plants in the system at the same time. 

The water tanks are 9.5 m3 each. We have an IBC tank as MMBR (1m3). The sump tank holds approximately 4 m2, but we normally use 2 m2 of the space. The cultivation troughs together hold approximately 23-25 m3 (depending on how high the water level we set). Together, the total system uses approximately 35 m3 of water. We also have an IBC tank that will be used as a quarantine for incoming fish and preparation tank before slaughter. 

On the far side of the building you can see the sump tank building (beyond the round fish tanks) and the blue cube is a three meter container that contains a diesel powered generator.

In the next blog post we will document our building process in a build logg.

The text in these posts are licensed under Creative Commons BY-NC-SA International.

Build an aquaponic indoor farm – part 1 – start and prior knowledge

This is a description of how we at Johannas Stadsodlingar (urban farms) and Concinnity together have built Johanna’s aquaponic pilot facility. We want to share how we did it and our thinking behind it. There is quite a lot to think about, so there will be several posts to cover most things.

Part 1 – to start, prior knowledge (this post)
Part 2 – design
Part 3 – building log

Three years ago, we at Johannas decided to start a company that produces food in circular production systems on a large scale. We started with fish and vegetables. The method we are going to use for this is called aquaponics. We have experience from cultivation and to start and run companies up to 100 employees. We have been studying circular cultivation systems for many years. However, we have not run an aquaponics operation before and we know that one of the problems people encounter when they start with aquaponics is that they often build a large-scale facility too early. You have to learn how to run an system which contains a mini-ecosystem with fish, bacterial cultures and vegetables. We decided to build a pilot plant at Husby farm in Vallentuna, north of Stockholm. Husby farm is owned by William, who is a partner in Johannas. We chose to use a third (290 m2) of a former dairy farm, which is about 900 m2.

William and Mikael in the old dairy farm at Husby.

If you are going to build an aquaponic facility, large or small, you should study first. We have three sources of information and inspiration that we can recommend. 

The ”basic course” in aquaponics is obtained from the UN’s agricultural agency FAO..It is a book in PDF format that you can download: Small-scale aquaponic food production, FAO 2014.

Small-scale aquaponic food production, FAO 2014.

Our aquaponics design is partly based on a description from the book The Aquaponics Farmer: A Complete Guide to Building and Operating an Aquaponic System, by Adrian Southern and Whelm King.

The Aquaponic farmer, Southern & King.

If you want to run an aquaponic facility on a smaller scale, say 1000 m2 of cultivation area. Then you might be able to cope with what you learn from the books. But we strongly recommend that you participate in some formal training, and example of this is the one-year course Fish and shellfish farming, which is a distance learning course in Sweden. Fish farming is the most sensitive part in aquaponics, and it can be very problematic if the fish dies. In addition, there are legal requirements in Sweden (and probably other countries) to have appropriate training in commercial animal husbandry.

Picture from the Swedish fish and shellfish long distance learning course.

We have also learned a lot from study visits, including at:

There are many more aspects of running an aquaponics facility that you need to have knowledge of. We decided to buid our pilot plant all by ourselves (with a few exceptions), primarily as we think you learn a lot from it. It is a lesson that is well worth it in our eyes, as we intend to scale up what we do much larger, and then we need to understand why things are designed as they are. In your team, you should have at least basic knowledge of the following:

  • Aquaculture
  • Vegetable growing
  • Water chemistry
  • Ecosystems
  • Sales and marketing
  • Business economics, such as accounting etc.
  • Food safety
  • Technical systems, such as pumps, oxygen meters, cooling, heating, etc.
  • Information Technology (IT) system

In our next blog post we will look at the design we picked and the changes we made along the way in our design.

The text in these posts are licensed under Creative Commons BY-NC-SA International.