Abstract: Disclosed are devices, methods and/or systems for use in protecting water flow systems from biofouling and/or other related contamination. One or more devices are introduced into the water flow system, such as downstream of the water supply (e.g., a lake, an ocean, a river, a water reservoir, or other water supply—including contained water supplies) and upstream of various surfaces/systems of the water flow system for which biofouling protection is desired. The device(s) include a defined volume for the water and at least one structure that is positioned therein in a use configuration so as to interact with the water in the defined volume to form “conditioned water” that passes downstream into the water flow system. Such devices prevent, limit, and/or reduce biofouling within the water flow system.