Sponge gardens are found on boulders in the deeper areas of the aquatic reserve beyond 8 m.
These gardens are rich in sea squirts, sponges, sea fans, small foliose algae, and the endangered cauliflower soft coral, Dendronephthya australis.
Common inhabitants of sponge gardens include leatherjackets, wobbegong sharks, giant Australian cuttlefish, eastern red scorpionfish, sea stars, and nudibranchs.