Aquaponics shows promise for African agriculture

Africa faces mounting food security challenges, and innovative agricultural solutions are becoming increasingly necessary. One technology gaining attention is aquaponics, a system that combines fish farming with crop production.

Martin Fick, originally from Beatrice, Zimbabwe, has spent 15 years developing aquaponics systems across Sub-Saharan Africa through his company, Practical Aquaponics SA. Operating from Makhanda (formerly Grahamstown) in South Africa's Eastern Cape, Fick combines commercial aquaponics operations with academic work as a lecturer in biochemistry, microbiology, and ichthyology at Rhodes University.

Fick's academic connection to Rhodes University and the JLB Smith Institute of Ichthyology provides him access to research on aquatic biodiversity and bio filtration. This scientific grounding influences his approach to system design, focusing on the biological processes rather than simple replication of online tutorials.

His interest in aquaponics began through consulting work with a Dutch organisation, where he met Professor Jan Oofman from Wageningen University's biotechnology department. Oofman introduced him to the potential of aquaponics as a sustainable business model. Fick's company has since installed systems in Zimbabwe, Angola, and Zambia.

Science behind the system

Aquaponics relies on biological processes to convert fish waste into plant nutrients. "It is biologically intense and you are using biology to generate nutrients," Fick explains. "So it's not easy like you just take something out of a bag and throw it in the water and it's not hydroponics."

The complexity of these biological systems produces food without synthetic chemicals, which can command higher market prices.

For Zimbabwe specifically, Fick sees significant potential. Aquaponics systems use approximately 2% of the water required by conventional farming, valuable in water-scarce regions. The systems don't require soil, making them viable where land has been depleted or contaminated. They also operate as closed-loop systems, producing no agricultural runoff.

Water contamination concerns Fick particularly. He points to recent lithium mining operations in Zimbabwe's Ruwa area discharging into local rivers. "That river is dead and it's going straight down into the Save," he warns. "It will eventually poison that whole system." Contaminated irrigation water creates health risks in conventional agriculture that aquaponics systems can avoid.

Small-scale implementation

Rather than large commercial farms, Fick advocates for small-scale urban systems that create micro-enterprises. "We can bring these things right into town, right into your back garden and build small businesses," he says. This approach aims to provide both food security and economic opportunities at the community level.

The technology's versatility extends beyond backyard operations as the nutrient-dense, organic produce from aquaponics systems is particularly well-suited for the hospitality industry, where restaurants and hotels increasingly seek locally-sourced, premium ingredients to meet growing consumer demand for farm-to-table dining experiences and sustainable food practices.

Fick's company operates an affiliate in Zimbabwe's Ruwa area and maintains a demonstration system in Glen Lorne, Harare, where potential users can observe the technology in operation.

Economic considerations

The technology's minimal infrastructure requirements and ability to produce crops year-round suit Zimbabwe's current economic circumstances. Systems qualify for carbon credits and operate within regenerative agriculture frameworks.

However, the biological complexity means aquaponics requires more technical knowledge than conventional farming methods. Success depends on understanding the interactions between fish, bacteria, and plants within the system.

Implementation reality

The technology faces practical hurdles. Initial setup costs, technical training requirements, and ongoing system management present barriers for widespread adoption. The success stories from his company's installations demonstrate potential, but scaling up requires addressing these implementation challenges.

For countries dealing with agricultural limitations, aquaponics offers one possible solution among many needed approaches to food security. The technology's water efficiency and soil independence address specific regional problems, though its complexity means it won't suit every situation or operator.

* Recently we shared a story on a hydroponic system. Whilst aquaponics and hydroponics are both soilless growing methods, they differ significantly in how they provide nutrients to plants:

Hydroponics:

• Uses synthetic nutrient solutions mixed with water
• Requires constant monitoring and adjustment of nutrient levels and pH
• Plants grow in inert growing media (like perlite, rockwool, or clay pebbles)
• Nutrient solution needs to be regularly replaced or refreshed
• More precise control over exact nutrient ratios
• Generally simpler to set up and manage initially

Aquaponics:

• Combines fish farming with plant growing in a symbiotic system
• Fish waste provides organic nutrients for plants through bacterial conversion
• Beneficial bacteria convert fish ammonia into nitrites, then nitrates that plants can absorb
• Plants filter and clean the water, which returns to the fish tanks
• Creates a closed-loop ecosystem that mimics natural cycles
• Produces both fish protein and vegetables simultaneously
• More complex biologically - requires understanding fish care, water chemistry, and bacterial processes
• Takes longer to establish (4-6 weeks for bacterial colonies to mature)
• Generally uses less water overall due to the recycling system

Key Differences:

• Nutrient source: Synthetic chemicals vs. organic fish waste
• Complexity: Hydroponics focuses on plants only; aquaponics manages fish, bacteria, and plants
• Products: Hydroponics produces only vegetables; aquaponics produces both fish and vegetables
• Sustainability: Aquaponics creates a more self-sustaining biological system
• Setup time: Hydroponics can start producing immediately; aquaponics needs weeks to establish

Both systems use significantly less water than traditional soil farming, but aquaponics typically uses even less due to its closed-loop design.