I'm managing a very tiny island in the middle of nowhere in Indonesia and we are planning on making a simple spa. I'd love to build a very simple pool (for 2 or 3 people), but the availability of fresh water is scarce as we produce our own with a desalinisation machine. We dont produce enough to maintain even a small pool, but since we have soo much sea water around us - is it possible to fill up a small pool with 100% sea water? How could you maintain such a pool?