</div><div style="clear: both"><br /></div><div style="clear: both">Stage 1: Colonization The journey of an eco reef begins with a <a href="https://www.ecoreefproject.com/what%20is%20terraforming.htm" target="_blank" rel="noopener">hard substrate</a>, such as a rock or a coral skeleton, which provides a surface for the colonization of organisms.