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Five diatom species were isolated from settlementplates at Southern Ocean Mariculture, Victoria,Australia (Naviculasp., Naviculajeffreyi, Cylindrotheca closterium, Cocconeissp., Amphorasp.) and tested insettlement experiments with Haliotis rubralarvae. Settlement was very low on single speciesdiatom films and varied between 1%–6%. Depending onthe species combination larvae preferred to settle onfilms with mixed diatom species than single speciesfilms. The highest settlement was achieved with amixed film of Naviculasp. and Amphorasp.Five and ten-day-old germlings of Sporolithonduruminduced settlement of the abalone Haliotisrubra. However, the settlement rate was significantlylower on germlings than on the whole thallus of thealga. Germlings inoculated with the diatom Naviculasp. induced higher settlement than films ofthe diatom species alone. High settlement of up to52% was also achieved with germlings of the greenalga Ulvella lens. Settlement was reduced onU. lenssquares inoculated with the diatom Naviculasp. but higher than on films of the diatomalone. The settlement rate was higher if plates withU. lenswere previously grazed by juvenileabalone.Post-larval growth rates were higher on monospecificdiatom films than on U. lensor on S.durum. The best growth rate was obtained with Naviculasp. U. lensand S. durumareboth good settlement inducers, but are notsufficient to support rapid growth of young H.rubrapost-larvae. Survival was low on U. lensand on the diatom C. closterium. We suggest thatcommercial nursery plates seeded with U. lenswill result in high and consistent settlement, whilean inoculum with Naviculasp. will ensuresufficient food for rapid growth of the post-larvae.