The paper presents the manufacturing technology for a water oxygenation device called further fine bubbles generator. The fine bubbles generator has a rectangular shape and it can create a screen of fine air bubbles. The manufacturing technology of the drilled board (the board with holes) and the manufacturing technology of the fine bubbles generator’s body are subsequently exposed. A non-conventional technology, namely electro-erosion processing, was used in order to manufacture the board with holes. Fine air bubbles are obtained by this method, increasing the oxygen transfer to the water mass.