What are games to play at an indoor beach parties?

Volleyball - If you have more than 2 people & a volleyball/beachball, this is a great game

Competitions - Diving competitions and underwater activities are good, like who can do the biggest splash or who can swim the furthest underwater or who can pick up the most coins from the bottom of the pool in 1 minute,

Races - Relays in teams are good, if not, just 2 people racing works fine too.

Octopus - One person is 'it', they stand in the middle and shout 'Octopus'. Everyone else has to try and swim past while the 'octopus' has to swim around and try and tag them. Anyone who is tagged is 'seaweed'. 'Seaweed' can move their arms and tag people but they can't move their feet.

Other Games - Marco Polo, Shark and Minos, and DeadGirl.