I'm in Sydney Australia with a rectangular pool 9m x 4.5m about 50,000 litres. After 30 years of good service my Polaris 360 died and my automatic chlorinator is on its last legs so I'm in the process of researching a suitable salt water chlorine system along with a "robotic" cleaner. I came across this site during my research and it looks like a good, unbiased, source of information.