ballast water treatment apparatus and methods for preventing foreign aquatic invasive species form entering marine ecological zones by translocation in ship &# 39 ; s ballast water . the apparatus includes a housing , a filter member , and uv water treatment chambers . methods include use of a ship &# 39 ; s fire hydrant system for moving ballast water from the ship &# 39 ; s ballast tanks into the apparatus for filtration and treatment . in - port service vessels and dock - side service vehicles are equipped with the treatment and filtration apparatus to provided in - port or dock - side ballast water treatment services . related methods are also provided .