During a match, players tread water or swim the entire game and cannot touch the bottom or sides of the pool, and only the goalie may handle the ball with two hands.
Players use an "eggbeater" kick--a circular kicking stroke used for stability and support in treading water. Similar to an alternating breaststroke kick.
The object is to put the ball into the opponent's net, similar to soccer. Play consists of four seven-minute quarters, with two-minute breaks between quarters. There is no elongated halftime.
Before the match, the team captains meet for a coin flip. The winner has the option of choosing his team's cap color (white or blue), or the end of the pool his team will defend. Play is started each quarter by a sprint: Each team lines up along its own end line, and at the referee's whistle, sprints for mid-pool, where the ball is floating. Players may not push off of the goal line at the start of the sprint.
The clock stops temporarily for the frequent fouls and after a goal is scored. There are not time outs. A goal is scored when the whole ball crosses the goal line between the posts and under the crossbar, provided an offensive player hasn't punched it across the line. Other than the fist, any part of the body may be used to knock the ball into the goal.
Upon taking control of the ball, the offensive team has 35 seconds to shoot or it loses possession. A shot clock at each end of the pool helps the players keep track.
Two meters from each end line is the aptly named two-meter line, which marks offside violations. No offensive player may cross the two-meter line unless the ball precedes him. A two-meter (or offside) call results in a change of possession.