Abstract: The present invention is directed to aquatic systems and methods for off-shore energy production, and particularly to systems and methods for generating large amounts of methane via anaerobic digestion, purifying the methane produced, and sequestering environmentally deleterious by-products such as carbon dioxide. The energy production systems contain one or more flexible, inflatable containers supported by water, at least one of which is an anaerobic digester containing bacteria which can produce energy sources such as methane or hydrogen from aquatic plants or animals. The containers of the present invention can be large enough to provide adequate amounts of energy to support off-shore activities yet are relatively easy to manufacture and ship to remote production sites. The systems can also be readily adapted to sequester carbon dioxide or recycle nutrients for growing feedstocks on site.