Bathing in a Pool on Shabbos

Shabbos afternoon turned out to be a warm day. Chaim and Levi were playing in the backyard. By 3 o'clock it was too hot for them to play anymore.

“Let’s go inside, Chaim,” said Levi.

“But there is nothing to do in the home,” replied Chaim.

“Well, at least we won’t be hot,” explained Levi.

“Hey! How about we swim in the pool?” proposed Chaim as he pointed to the pool that was standing in their backyard.

“We cannot swim on Shabbos,” replied Levi.

“Ok, so we won’t swim there. We’ll just enjoy being inside the cool water of the pool,” said Chaim.

Bathing in a Pool on Shabbos

Question: Can Chaim and Levi bathe in the pool now?