Aries: Starts a water gun fight with Sagittarius

Taurus: Plays with the little kids in the shallow end

Gemini: Sees how long they can hold their breath underwater. Aquarius eventually gets worried and checks on them.

Cancer: Cannonball!!

Leo: Immediately goes to the diving board and drags Pisces along with them

Virgo: Handstands and back flips!!

Libra: Laps yooo
Scorpio: Accidentally swims into Virgo doing handstands and back flips

Sagittarius: Aries challenges them to a water gun fight and they get destroyed

Capricorn: Cheers on Libra At least someone cares about meh!

Aquarius: The lifeguard

Pisces: Gets dragged to the diving board by Leo