A natural swimming pool gives us the sense of a natural spring before we contaminated all our water sources. Its water is clear, supports life and is based on the multiple cleansing effects of constructed wetland. The water in the pool does not contain chemicals and is pleasant to touch and drink. According to the US Ministry of Health, whereas chlorine (at the permitted level) only protects users against 15% of diseases (!!), a biological system offers 85% protection against these hazards, without putting our health at risk with cancerous chlorine by products such as chloramines and metallochlorides.