Scientists Turn Fish Waste into Fertilizer for Sustainable Farming

Scientists at the Council for Scientific and Industrial Research-Water Research Institute (CSIR-WRI) have developed a system to convert fish waste into fertilizer for farming. The integrated aquaculture-agriculture system aims to boost food production while reducing pollution from fish farming wastewater.

Fish Waste Converted into Fertilizer

The system involves assessing the nutrient content of wastewater from fish production and using it to grow crops according to their nutrient requirements. Dr Seth Agyakwah, Head of Aquaculture at CSIR-WRI, disclosed this at the Institute's 2026 Mid-Year Review in Accra on Wednesday. He explained that the Integrated Agriculture-Aquaculture System seeks to make better use of limited water resources and reduce waste.

CSIR-WRI Seeks to Address Water Scarcity

The approach is particularly relevant to fish farmers using earthen ponds, concrete tanks, reservoirs, and tarpaulin tanks, who often discharge wastewater without considering its potential for crop production. Dr Agyakwah said the technology was developed to help address environmental and health risks associated with the use of polluted water for vegetable production. He noted that some farmers used water from gutters to irrigate vegetables, potentially exposing consumers to harmful contaminants, including heavy metals.

Trials Produce Good Yields

Dr Agyakwah said trials had produced good yields, including cucumbers, demonstrating the potential of the system to support food production. He added that the technology could also serve as a climate-smart intervention by helping farmers make productive use of available water and reduce their vulnerability to climate shocks. The Integrated Agriculture-Aquaculture System has been transferred to some youth, women, and men through training supported by the Economic Community of West African States (ECOWAS) and the West and Central African Council for Agricultural Research and Development (CORAF).

Addressing Access to Financing

Dr Agyakwah appealed to the Ministry of Food and Agriculture to consider the integrated system as a model for food production, particularly in areas facing water scarcity. He also noted that access to financing remained a major barrier to commercializing the technology. The beneficiaries of the technology have been supported to develop business plans and entrepreneurial skills, but they still face challenges in accessing the necessary funds.

Inter-Institutional Collaboration Key

In a separate presentation, Dr Sylvester Afram Boadi, a Research Scientist at CSIR-WRI, called for improved coordination among institutions responsible for water, energy, food, and environmental planning. He suggested that the National Development Planning Commission (NDPC) could lead cross-sectoral planning to ensure that infrastructure projects delivered benefits across the water, energy, food, and environmental sectors. Dr Boadi proposed stronger inter-institutional collaboration to address the fragmented planning that often results in missed opportunities.

A Path Forward

The CSIR-WRI's Integrated Agriculture-Aquaculture System is a significant step towards reducing pollution from fish farming wastewater and increasing food production. While access to financing remains a major challenge, the system's potential to support food production and reduce environmental pollution makes it a worthwhile investment. As the Ministry of Food and Agriculture considers the integrated system as a model for food production, it is essential to address the access to financing barrier to ensure the technology reaches its full potential.

Source: JOY