Biorock, also known as Seacrete or Seament, is a trademark name used by Biorock, Inc. to refer to the substance formed by electro-accumulation of minerals dissolved in seawater. Prof. Wolf Hilbertz developed the process and patented it in 1979. The building process, popularly called accretion, is not to be confused with Biorock sewage treatment. The biorock building process grows cement-like engineering structures and marine ecosystems, often for mariculture of corals, oysters, clams, lobsters and fish in salt water. It works by passing a small electric current through electrodes in the water. The structure grows more or less without limit as long as current flows.