John wrote:


Regarding your comment about poly tanks not all needing flat bases - I am
aware of one manufacturers products which are as you describe but they are
generally harder to source and not all that popular. I did once come across
a plastic tank (standard type) which a builder had placed on two plinth
walls. It looked odd as I approached it and I found that the bottom had
slowly stretched under the weight of fuel until it had ballooned down to
touch the ground. All we could do was replace it before it burst. The
annoying thing for the householder was the label giving instructions for
support was still attached to the old tank at that time


Mmm. I hve a two wall support...and five lintels just laid across it.

Perfect.