“We’re building a commercial facility and a unique space to bring partners together and see the technology in motion,” says Steve McArthur, chief technology officer at Pontus Protein Ltd (i.e., Pontus).
Pontus is a vertical aquaponic farm in British Columbia that combines the production of rainbow trout with that of water lentils, the latter being aquatic plants that are packed with protein. Water lentils contain 42.1-50% plant protein by dry weight, with the exact protein content dependent on the strain grown. Moreover, different strains have unique nutrient profiles with some having particularly high levels of Vitamin B12, iron, potassium and calcium.
As an aquaponic system, rainbow trout are raised in one section of the facility while water lentils are produced in large shallow trays in another room, the two sections connected by the exchange of water. Nutrient-rich water from the fish farm is circulated to the water lentil production zone, where the nutrients are extracted by the plants. The filtered water is then recirculated to the fish basins, completing the loop.
According to Steve, Pontus’ 20,570-square-foot flagship facility has an annual production capacity of 10.5 metric tons of rainbow trout and up to 11.3 metric tons of dried water lentil powder. Aside from the fish farm and water lentil production rooms, the facility has administrative spaces, a commercial kitchen and rooms for water lentil processing from rinsing to packaging. The flagship farm is currently under construction, although the production spaces are expected to be completed in the coming months.
Water lentils: a fast-growing plant protein source
Water lentils are small aquatic plants that produce asexually on the water surface, with a mother leaf spawning two smaller fronds which then produce two fronds of their own, and the process continues. This exponential growth means that Pontus’ water lentils can be harvested every 24h. As Steve explains, Pontus can harvest 30% of the grow bed’s width in a single day, only to have it completely refilled by the following day.
“There is no seeding or pollination required; it’s just basic biology at work. And the exponential growth means that we need to stay on top it to prevent them from outgrowing the grow beds, which are 144 feet long, 8 feet wide and 7 inches deep,” explains Steve.
Harvesting is done using Pontus’ patented robotic system called HARV (photo below), which rides on rails along the beds and inserts its “nose” into the cultivation area to lift out the water lentils with a conveyor system. This system facilitates the harvest overall, but especially at height as the grow beds are stacked 25 feet into the air.
Biosecurity a top priority
As Steve explains, the combination of fish species with plant production makes biosecurity particularly important to maintain. At its flagship facility, the company has installed two air showers: one near the fish farm entrance and the other near the water lentil production zone. Anyone entering the rooms passes through these showers to knock off any pests, particulates, or spores that may be on their clothing. A foot bath also prevents entrants from carrying materials in on their shoes. Additionally, the farm has standard operating procedures to ensure that sanitary measures are strictly followed.
6.3 times more fish
With its flagship facility nearly completed, Pontus is already looking ahead to its next facilities which will span 62,000 square feet and roughly 450,000 square feet each. The 62,000 square foot facility, the design of which is still being finalized and is next to be built, is expected to produce 66 metric tons of fish per year or roughly 6.3 times the capacity at Pontus’ flagship farm.