David Pagan Butler makes amazing organic pools. He designs each one as a closed environment that supports itself. From the mineral content in the water, to the animals that visit the plants and algae, everything is designed to keep the water safe for both plant life and human life. Now you might be hesitant to try and swim in a natural pool. But since the ecosystem is so tightly regulated, dangerous pathogens like E. coli and harmful amoebas find it a very hostile place to live. Organic pools also come into several designs.Natural pools are similar to the chlorinated counterparts in size and depth, while plunge pools are smaller and easier to fit in modest spaces.