Swimming Pools are typically measured in yards or meters. Competitions are usually held in 25 yard, 25 meter, or 50 meter pools.
Meters.
You would use meters.
Kiloliters or gallons depending on sizeo f the pool.
You would use cubic meters or cubic feet to measure the volume of a swimming pool. This unit accounts for the three-dimensional space that the pool occupies.
Litres.
Liters or cubic meters are typically used to measure the volume of water in a swimming pool.
You would use meters.
You would be more likely to measure a fish tank in centimeters because it is typically smaller and requires more precise measurements. A swimming pool, on the other hand, is usually larger and would be measured in meters or feet.
It depends where you are. The term I find most common is Gallons.
The base unit of volume is the cubic metre.
yards, feet
I would use meters to measure the length and width of the pool as it is a more appropriate unit for smaller measurements like those typically found in swimming pools. However, if the pool is very large, kilometers may be more appropriate.