Respiration is a key variable to understand the flux of energy and matter in any ecosystem. In fact, ecosystem respiration is a critical component of the carbon cycle and might be important in regulating biosphere response to global climate change. Respiration is the basic process used by the biota to yield energy from the degradation of organic matter for their survival needs, its measurement provides an estimate of the minimum energy needed by the organism. Accordingly, the total respiration of an aquatic community can be equated to the minimum energy needed to maintain its organized living structure and function. Despite its importance, community respiration has been a process scarcely studied in the ocean and only during the 90's has become more relevant. In fact, whereas aerobic metabolism has been scarcely studied in ocean systems, anaerobic metabolism, especially at the community level of organization, has been largely neglected.