Several ball types have been used throughout the game's history. These include a 10-pound pool brick, a junior sized NFL-style football, and a junior sized basketball, all with negative buoyancy. Pneumatic balls (such as the football or basketball) can be made negatively buoyant by filling them with a liquid that is denser (heavier) than water instead of air, e.g. a strong saline solution or corn syrup.
The sport is similar to water polo, but it is played most of the time underwater. Each player can go up to the surface to take air as many times needed, except when he has the football in his hand.
Like the traditional football, one player from each team manoeuvre the ball past their opponents to get to the ball to goal. Each team has 13 players, but only five players are on the court at same time. The player with the ball can swim with it or pass the ball to his team players. Meanwhile, the opponents will try to take the ball from the other player or intercept a pass. And at last the team which has the maximum scores will win.
The court is 10 metres wide (32 ft), 15 metres (49 feet) long, and 4 metres (13 feet) deep.A match has two 20-minute rounds, and a half-time of 5 minutes.