We are just finishing up on a rainwater catchment system on our house
and our first big decision was what kind of tanks to use.
Of course we would have loved to have had nice galvanized tanks,
but the reality is that the above ground polyethylene tanks we chose were more affordable,
are easier to handle and install, are able to be moved,
and will last much longer than the metal.
Many people go with below ground tanks but that requires different tanks,
and the added cost of digging not to mention the disruption to the landscape,
and the added factor of pumping the water back up to the point of use.