There has been a dramatic decline in Ecklonia radiata populations along the Great Southern Reef. Active restoration methods may be required to rebuild lost E. radiata populations. Current restoration methods require the cultivation of kelp under hatchery settings and due to the complexities and variability of kelp life histories to abiotic factors, progress in hatchery optimisation has been limiting. This study focused on testing the effects of nutrient concentrations on the early-stage sporophytes of E. radiata from two populations located in Port Phillip Bay, Victoria. Three levels of nutrients were added to early transitioned sporophytes and growth was recorded over 21 days. Nutrient treatments were based on open ocean nutrient levels (treatment 1), average nutrient levels in Port Phillip Bay (treatment 2) and standardised culturing media levels (treatment 3). Average sporophyte growth was high across sites and treatments with no significant difference between nutrient concentrations on growth. Results indicate small amounts of nutrients can be added to hatchery cultures without compromising early growth stages of E. radiata therefore, reducing hatchery maintenance time and culture contamination. This study contributes to establishing a comprehensive, localized hatchery protocol for E. radiata populations that will help inform active restoration efforts in Port Phillip Bay.