Reef Balls

Reef balls are made using a special mix of concrete that allows algae to grow quickly, creating ideal marine habitat for fish and invertebrates. According to the web page found at http://www.reefballaustralia.com.au/ , Reef Ball Australia “design and build:
Artificial reefs for fishing, diving, snorkeling
Reefs for beach protection and tourism, e.g. multipurpose breakwaters
Fish friendly structures for coastal developments, jetties, resorts, marinas
Man-made reefs for offsetting environmental impacts, coral restoration
Reef Balls are a scientifically proven concrete artificial reef unit now being used in over 59 countries to enhance, protect and rehabilitate reefs and beaches. The key to their success is that they mimic natural reefs in form and function, quickly increasing fish numbers and diversity as well as being rapidly colonised by corals, algae and sponges.
Reef Ball Australia is the authorised Australian contractor for the Reef Ball technology. Over half a million Reef Balls have been deployed in over 59 countries and 3,200 projects. Reef Ball Australia’s services include: Supply of concrete artificial reef units, Site assessment, Reef design,
Assistance with permits, Deployment, Coral rehabilitation, Monitoring. Wikipedia has a page about the Reef Ball Foundation at http://en.wikipedia.org/wiki/The_Reef_Ball_Foundation.