This article reviews critical aspects of the aquafeed value chain in the Kenyan aquaculture sector. Aquaculture production in Kenya has grown steadily in recent years, to more than 18,000 tons in 2019. Due to the growing demand for fish and fish products, there has been a gradual shift from extensive to semi-intensive to moderately intensive aquaculture systems, leading to an increased demand for high quality commercial fish feeds. The current annual demand for fish feed in Kenya is estimated at 34,000 tons. It is the lack of sufficient and high-quality local fish feed production that has created a market for fish feed importers, which is currently estimated at 7,000 tons annually. However, the imported fish feed is expensive for most fish farmers, leading to low production. Local fish feed production through home-based formulation should be driven by fish farmers to contain the rising cost of feeds. Most cottage feed manufacturers produce mash, crumbles or sinking pellets because they lack extruder for making floating pellets, hence the need for quality control in the aqua-feed sector. Fish feed producers are weakly covered by financial services providers, hence the inability to compete effectively with other value chains. The paper outlines five key actors in the aqua-feed value chain from production to marketing. These include; raw material (ingredients) suppliers, feed manufacturers (feed formulators), distributors/wholesalers, retailers, and customers who are fish farmers. We recommend intensification of local aqua-feed production using locally available materials to reduce the importation. This will ensure the long term economic and ecological sustainability of the aquaculture sector. There is a need for favourable policies to lower importation rates for raw materials as a way of boosting the availability of additional feed resources and inputs.

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Aquaponics incorporates aquaculture with hydroponics, whose principles and operations largely remain untested. Currently, there is a knowledge gap on the performance of aquaponic systems used for fish production under different stocking densities. This may hinder adoption and generally retard the development of aquaponic culture systems for fish and vegetation production in Kenya. The objective of the current study was to determine the effect of fish stocking density on the growth performance of lettuce (Lactuca sativa) and Nile tilapia (Oreochromis niloticus) reared in a coupled aquaponic system. We used three fish stocking densities of 150, 300 and 450 fish m −3 , each replicated five times. For each treatment or fish stocking density, 16 lettuces were planted m −2 as the planting density. We monitored the following water quality parameters to determine the effects of fish stocking density on water quality; pH, total ammonium-nitrogen (TAN), nitrates (NO − 3 ), nitrites (NO − 2 ). In the different stocking densities (450, 300 and 150 fish m −3 ), the water quality parameters ranged from dissolved oxygen: 4-7 mg L −1 ; pH: 6.3-7.3; TAN: 0.32-0.57 mg L −1 ; NO − 3 : 0.13-0.36 mg L −1 and NO − 2 : 0.020-0.046 mg L −1 . The final weight of the Nile tilapia fingerlings was 25.2 ± 4.2, 32.0 ± 3.8 and 42.6 ± 3.1 g for 450, 300 and 150 fish m −3 , respectively. The biomass of lettuce was statistically different (p < 0.005) and increased with increasing stocking density as 166.4 ± 9.8, 276.8 ± 23.2 and 304.6 ± 23.2 g for 150, 300 and 450 fish m −3 , respectively. Adopting the intermediate stocking density of 300 fish m −3 , which gave the best performance of the aquaponic system, is therefore highly recommended.

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