The essential idea that distinguishes natural swimming pool from the conventional ones is the functioning of the pool through naturally maintained system and the biodiversity featured by the pond. Basically in human designed natural swimming pools, there are two zones one for filtration and the other for swimming. On top of this, the ratios, size and design might vary between ponds during planning and construction.
Ideally you must plan a natural swimming pool between 30 and 60 square meters on the whole. At the same time, note than there are much smaller ones that are running successfully throughout when maintained properly. The ratio of division between the swimming zone and the filtration zone could e anywhere between 50: 50 and 70:30. The shallow areas of the ponds shall feature a rich plant life and aggregate in a way functioning as natural filters. This is why the water remains clear and clean in a natural swimming pool.
To see that plants grow in abundance without any challenges, it is important you maintain the pH levels of the water in the pool between 5.5 and 7. The location and design of the pool is something very important that can help in saving on maintenance costs as against the conventional kind of pools. Know that the larger the pool, the lesser will be algae growth. Also, deeper pools have cooler waters. Though this might not be a good thing during winter, you will find it soothing under summer. The lesser a pool is exposed to sun light, the lesser are the chances for algae growth. Keep this in mind while designing your pool as this is essential even to protect the aquatic life.