SeedCare From Oosterleek Uses Bioreactor For Clean Water

Healthy water is literally of vital importance to Mark Keulen of seed production company SeedCare. He has had a bioreactor on his farm for five years, which provides clean water with good bacteria, which gives him a more resilient plant. “Good output water is extremely important.”

He opens a drawer. There are some light blue bags inside. He opens one and shows the contents. Pink grains of ‘strawberry seed’, owner Mark Keulen points out. Another late one. Next to dried buds lies chestnut-colored powder. “That is the harvested seed of our begonias. If you consider that we are paid per gram, you understand how important the parent lines are for our hybrid seed productions.” At the same time, the parent lines are also the weakest lines, he adds immediately. “We cross a super homogeneous male white plant with a super homogeneous female red variety, resulting in a tight hybrid. If those parent lines no longer produce seed, then our work will not be paid. Hygiene, including water quality, is therefore literally of vital importance to us.”

Focus on water quality
Cologne is the third generation at the 2-hectare seed production company SeedCare from Oosterleek. The North Holland company consists of about twenty departments, the smallest of which is 40 m² and the largest 2,000 m². “We grow all kinds of ornamental crops and greenhouse vegetables here for third parties,” he says. “From tomatoes to primulas.” The diversity is great. Primroses, for example, are grown on behalf of various customers, which means that Cologne sometimes has more than fifty different crossings in a department, consisting of thirty sire lines and thirty dam lines. “It’s all quite complex,” he summarizes.
This complexity is reflected in its water management. In addition to drip irrigation, the seed propagation company sometimes has three to four different watering systems within a department. He is therefore extra focused on good water quality.
“Good output water is extremely important. I never believed in the principle of heating and disinfecting. With UV and ozone you kill all bacteria in the water, including the good bacteria. The water is clean, but also empty. In my opinion, this makes the plant more vulnerable. I prefer resilient water, which also ensures a more resilient plant.”

Switch to bioreactor
Twenty years ago he was one of the first to use a biological lava filter to disinfect his pool water, but this alternative still caused a lot of maintenance: biofilm in the pipes and wear on moving parts. So when Agrona experimented with the bioreactor about five years ago, Cologne was at the forefront.
The basin water first runs through a fine fabric filter. It then enters the bioreactor where the water flows along a floating membrane with bacteria. This reactor also contains an aeration system, the so-called Oxybull system, which adds maximum oxygen to the water. “The bioreactor was developed based on the idea that useful bacteria are preserved by adding a catalyst, the so-called AG STIM, and a high oxygen content,” says owner Nadir Laaguili. “The bioreactor treats the water. You can see it as the breeding ground for good bacteria and it ensures the breakdown of pathogenic fungi, so that Pythium, for example, hardly stands a chance. In the bioreactor, the good bacteria are already activated before they arrive at the plant, so when they get there, they can get to work right away.”

High oxygen content
The aeration system ensures maximum addition of oxygen to the water. The clean water runs from the reactor either into the pipework or to the clean water tank. Because the water is super saturated, the grower loses the biofilm in his pipes and the disease pressure decreases. “Due to this aeration system, the water moves continuously and is supplied with oxygen. As a result, there is no algae growth, among other things,” explains Laaguili. It has been known for some time that a high oxygen content leads to a higher yield. “It makes the drip lines cleaner and the beneficial bacteria ensure that the plant absorbs the nutrients more easily.”

Maintenance free
Cologne was quickly convinced of the effect. “I ran it side-by-side with the lava filter for a while, but soon I switched to the bioreactor. The disease pressure is nil. I really see more vital plants that are more happy.”
In addition, the system is maintenance-free. “With a UV filter you still have to keep an eye on the lamps and replace them in time,” says the seed propagator. “This system just works 24/7. In addition, I have never had clogged pipes or nozzles. We have no residue, we don’t have to rewind anything. It is a matter of setting up and connecting.”
All that required effort and time was figuring out the right capacity and flow. The seed production company has a system that can process 9 cubic meters of water per hour. Cologne runs continuously at 2 cubic meters per hour. “Considering the amount of water I need per day, this is enough. More could also be done, but I believe that the slower the water flows through the bioreactor, the more time the bacteria have to attach to the water, making the water extra clean.”

More awareness
The supplier sees an increase in demand for the bioreactor in greenhouse horticulture. There are now two systems running in the Netherlands, at this company and at a tomato grower, and several already abroad.
“Traditionally, growers have been very focused on disinfection by heating,” says Laaguili. “But I notice that more and more growers are realizing that killing everything is not the future. Research by Eurofins Agro shows that companies that completely disinfect everything are more susceptible to fungi. Their plants no longer have any resistance.” The usefulness of good bacteria is increasingly recognized, he says. “There is still little knowledge of useful bacteria, but there is still a lot to be gained from this.”
In addition, it is cost-effective. According to Laaguili, the purchase and installation of a bioreactor costs one third of a UV installation. In addition, a subsidy is available, which means that the grower gets back 20% of the investment.
The seed propagator: “My plants look vital. We have no problems with the root environment, we are no longer bothered by Pythium or Phytophthora. Healthy water is simply the most important thing. No UV or ozone is required for this. Keep it simple, I would say.”

Text and image: Marjolein van Woerkom