How do many sessile (attached and non-moving) benthic organisms colonize new areas of the ocean bottom?

Sessile organisms reproduce in a form of asexual reproduction or through budding. Fertilized organisms or larvae, which were once attached to an organisms body, are dispersed into the water and finds a new substrate then lives on its own. The chance on where a new organisms would thrive is determined by outside sources such as water current or movement. 

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