Setting optimal diet ratios of kelp (Ecklonia maxima (Osbeck) Papenfuss) and formulated feed, and tests of a recirculating system using Ulva (Chlorophyta) as a biofilter, in South African abalone (Haliotis midae) cultivation

Includes bibliographical references (leaves 129-161).Land-based abalone aquaculture in South Africa, based on the local species Haliotis midae, started in the early 1990's and has grown rapidly in the last decade. This has led to numerous studies into various aspects of farming H midae. There are two aims of this study, (i) to test the relative benefits of different ratios of kelp and the formulated feed Abfeed(R) K26 (feed component), (ii) to test the suitability of farming H midae with 50 % and 75 % recirculation rates (recirculation component) in an integrated system using the green seaweed Ulva as a biofilter. Aims for both components were to investigate the performance of the systems in terms of health of abalone, growth rates of abalone, sediment loadings and water quality. Both components were conducted on Irvin & Johnson Ltd Cape Abalone farm in Gansbaai, 140 km east of Cape Town