Artificial reefs are known for many purposes and are also considered tools. These experienced divers tools are used by many conservationists for the restoration of coral reefs all around the globe.
Over the past many many years these artificial reefs are getting popular among the tourists mostly and this is also helping with overcrowding.
Cons of Artificial Reefs
Over the years, artificial reefs have a lot of praise but a lot of criticisms from scientists who see it as a technique that involves working on the symptoms and not the problems that cause the loss of coral reefs. Some of the cons of artificial coral reefs are listed below-:
Toxic material – It can happen that the material used for construction might get toxic. Like the rubber and metal will degrade with time and corrode releasing toxins into the water causing pollution and harm to the marine diversity.
Tires as a material- In one of the attempts tires were used wherein a large number of tires were sunk into the ocean floor in different countries. This idea was thought of as a great initiative as it was a way to recycle waste into something productive but it didn’t work as planned because it didn’t provide a good structure on which the corals could attach. Also, during storms, the tires might get loose and might wash up the natural coral reefsÂ
Overfishing – it is a misconception that artificial reefs increase fish biodiversity. They rather concentrate the fish around a specific area. This makes the fishermen catch the fish easily and therefore might increase the problem of overfishing instead of helping the marine life.So to protect the reefs fishing should be allowed in a particular area.
Difference between the artificial and natural reefs – The artificial reefs differ from the natural ones in the trophic structure, biomass and in their multivariate composition. Hence, they might not be a suitable replacement for coral reefs. Also, it is believed that artificial structures might attract fish from the natural reefs and hence creating an imbalance in the habitat.
Materials Used for Artificial reefs
The best material for an artificial reef or an ideal artificial reef is:
Stable in adverse climatic conditions like storms.
Made from long-lasting, solid, non-toxic materials
The material should have a high surface complexity which helps in the attachment of corals, sponges, and other organisms
Designed to either blend in with the natural reef or be designed to stand out as sculptures and art.
Factors like depth, placement, boat navigation are also equally important for the success of an artificial reef
Some of the techniques that have worked for artificial reefs are as followsÂ
Wrecks and other large steel structures
Concrete structures-
Modular units ( glass and cement )
 Mineral Accretion devices
 Among the materials used for artificial coral reef structures, the best material for artificial reefs is concrete.
Concrete is the favourite material to use  the reason being are listed below -:
 It has a composition similar to natural coral limestone
 It is heavy, cheap, and readily available all over the world.
It can be moulded into different shapesÂ
And lasts a long time under the ocean.Â
Artificial reef companies
Some of the artificial reef companies that are working towards coral restoration are listed below as follows-:
Reef Design Lab-This non-profit organisation has brought the largest artificial coral reef in the Maldives. The Reef Design Lab identifies the reefs native to the region by using computer modelling software and further work on 3D printing to make 220 moulds that were cast in concrete and placed in the sea then assembled the entire structure.
The University of Hong Kong-In the university of Hong Kong the architects and scientists have come up with 3D printed tiles that attach to reefs and improve their chances of survival.Â
The Caribbean Marine Biological Institute (CARMABI) Research Station- Many scientists are looking in the hope that nature will help them in understanding how they can make these 3d printing reefs and those reefs will pay off too. Kristen Marhaver, a Marine Biologist and her colleagues tried using 3d printing. This method has allowed building many samples in a quick time so the place can be found to hook the anchor.
The University of Cambridge and the University of California San Diego-the researchers from the university are using bioprinting to produce reefs. The technique has the benefit over other techniques as it mimics the functional and structural traits of coral-algal symbiosis. In the process, the university did 3D scanning of living coral and then bioprinting replicas were made from polymer gels and hydrogels filled with cellulose nanomaterials to copy the optical properties of living corals.Â
Conclusion
These artificial 3d printed reefs have shown great popularity among the people and with its interesting design, if they are all over the place this will help when the crowd is in high amount and they have nowhere to go.