If you’re wanting to “get off the grid” altogether and not rely on mains water for any of your water needs then you’ll need a 50,000 – 100,000 litre rain water tank. However, it’s not recommended that you use rainwater for drinking in built up suburban areas.

If you’re aiming to keep your garden green all year round then you’ll need a 2000 to 4000 litre rain water tank depending on the size or your garden. You’ll also need a pump fitted to your water tank if you’re using a sprinkler system.

The toilet and laundry consume the greatest amount of water in the home, so if you’re plumbing a rainwater tank into these areas, you’ll want to go for a larger tank.

You can find cheap rainwater tanks through our Water Tanks ebay listings page . Just remember, in most cases you'll have to pickup the water tank or pay for delivery so buy a tank from a local distributor.