I wish to drink rain water and not the water that arrives by water main.
I wish to know the mechanism by which I can simply and easily change over source.
Presumably a one way valve should be installed.
The rain water tank will supply the whole house whilst the main water can be used for the garden.
There are some things to consider if you are using your rainwater tank as your main source of water for your house. One of the most important things to consider is the water safe to drink? Proper tank maintenance and decontamination of the water in the tank is important. If you're worried about the water from your mainline you could install a Stefani Whole House Filter System in combination with a Stefani Filter Undercounter Triple Stage. However, before you purchase any parts, I suggest checking with your local council on the rules and regulations regarding using your water tank as your main source of water.
You can install a manual system where you shut off the mainline and redirect the water source to your water tank. Some systems have an auto-top up from the mainline when there is not enough rain and your water tank is getting dangerously low. However, if you're not keen on this type of auto top-up, your only option is to filter the water.
If you need further assistance, please let us know.
Before you under take any changes to your drinking water supply you will need to answer a few question.
Do you live in the city / suburbs?
do you live rural?
do live in the remote areas/
if you live in the city you will be governed by state laws
if you live in rural with to tap water you will be governed by local laws
if you live in remote areas well you take what you get ground, tank water what ever is available
So I suggest you chase up the local laws that govern water supply
If you are using tank water for toilets, laundry or gardening and topping up a tank for this purpose there are no issues if any. The device need for filling the tank is a water tank auto fill valve
here is a link for an auto switching valve