Off the top of my head, Monier and Aura Lite are two brands who have rainwater harvesting systems. Rainwater is relatively clean depending on how clean your roof and gutter is but it is definitely non-potable.

Considering how water insecure we are even with our tropical climate, harvesting rainwater on your own now and self treating/filtering in the future doesn't sound too bad an idea.

Here's a checklist for inspecting and managing rainwater safety and quality. Pretty useful.

This post has been edited by OneMoreDay: Nov 6 2014, 11:56 AM

Bravo. Chlorine is the easiest way of treating water but it's hardly the healthiest solution.

We had loads of koi before in a rather deep pond. Hardly any mozzies. Then again we had fountains that kept the water from being stagnant the pond was filtered.