“Stellenbosch University is one of the best universities in the country and I was fortunate that I could do my PhD there,” says Oyama Guwa, a December 2020 PhD graduate at Stellenbosch University.
Originally from Mdantsane, East London, she is a biologist by training. “I did my PhD in Chemical Engineering, because a topic I was interested in was offered in that field.”
Her research topic was Developing novel aquaculture feeds specifically for aquaponics.
“The reason why I chose Stellenbosch for my PhD, is that I have always wanted change. I was born and raised in the Eastern Cape and I also completed all my studies there. Stellenbosch University being one of the best universities in the country was a great choice for me. I was fortunate that right after I finished my MSc in Zoology an opportunity in the field I was interested in was advertised in the Department of Process Engineering. I have always known that I want to do research, mainly because it challenged and pushed me and gave me a sense of purpose, especially the type of research that has the ability to improve people’s lives.”
Dr Guwa’s research is aimed at improving the overall efficiency of aquaponics systems by using fish feed additives. The feed additives were included in fish feeds with the aim of benefiting both fish and plants in the aquaponics system.
This doctor in Chemical Engineering is not only a biologist – she is also a wife and mother. “I have a 7-year old who is in Grade 1. So, during lockdown I spent a lot of time home schooling him and working on a manuscript for publication. Without my family and my husband, Lihle’s, support and love, I would not have been able to complete my studies. I also had two supportive supervisors, Dr Neill Goosen (Department of Process Engineering) and Dr Khalid Salie (Department of Animal Sciences), who were so understanding, especially during the lockdown when I had to shift my attention to home schooling.
“I am currently working with an aquaponics farm in Hopefield called Veggietails Aquaponics and planning a postdoc at the Animal Sciences Department on further research in the aquaponics field,” she concludes.
Title: Developing novel aquaculture feeds specifically for aquaponics.
Summary: An optimum source and inclusion level of iron and potassium from fish feed additives for optimising the production of African catfish was determined while simultaneously evaluating excretion of effluent that can be used to optimally grow plants in aquaponics systems. It was concluded that the addition of minerals through fish feed additives can reduce or even eliminate the need to supplement plants with nutrients in the form of nutrient solutions. The improvement of plant growth through dietary feed additives of fish in aquaponics systems can improve the efficiency of integrated aquaponics production systems.
Photographs: Dr Oyama Guwa at Stellenbosch University’s Welgevallen Experimental Farm conducting aquaponics trials with lettuce and the African catfish.