You can change the patterns at the bottom of the pool, but the water will still look very clear and a bit unnatural.

One solution is to fully decorate your pool with flooring, plants, or walls around it. With this approach, the water gradually appears different, giving you a more realistic effect.

Here you can see the difference between the top pool and the bottom one, using the same pattern:

The result of the top pool is:

Hope you like it !