Rules of water polo changed repeatedly for decades. Were exposed to frequent changes not only rules of the game, changed as well the equipment for water polo. The equipment for water polo was diversified and enriched qualitatively eventually. So there were marking, a board, wave canceling paths, color markers, etc.
When water polo only arose, to platforms for game wasn't imposed special requirements – its sizes were any, and even at all represented an uncertain site of a natural reservoir. Or it was that pool which happened nearby. Anyway, according to modern rules the pool water polo has to have depth not less than 1,8 m and the following external marking: 30 by 20 meters for man's and 25 by 17-20 meters – for female and youthful.