Look a little closer. 

 

The pool actually has 3 sections. The first is a large, shallow, shaded section that comes into the house, and is brilliant for smaller kids whose swimming skills are still a work in progress. If a kid can stand, then this section allows lots of pool-based play without needing to swim or tread water. And being under shade most of the day is a huge relief to parents whose kids equivocate the sunscreen-application process to torture. :)

 

The second is a medium-depth area (waist high on most adults and usually shoulder-depth for kids 5 to 6 +). A favorite spot to play chicken or water polo, or to loll and gab. In full sun. 

 

The third is full-depth, but has a sneaky shelf to stand on around the perimeter. In full sun except for late afternoon. 

 

The second & third sections together allow enough room for laps. 

 

The pool isn't heated (no need; the equitorial sun does all the work) and is treated with a gentle saline system.