When I built my pond and pump system some years back the tubing I was sold was a clear polythene type material - I still have a long length which is used on occasions when I decide to pump the pond out.
I've won a collection of bits of 25mm OD Aluminium tube (a collapsed fruit cage - the owner didn't take the roof netting off and the snow destroyed it), and was thinking of using them for a larger size cloche system. I found that the 25mm poly tube fitted over the Al tube fine and would bend nicely and clearly be good for making the top of the cloche support.
Unfortunately it now seems that the pond world has gone to a corrugated type plastic tube and I'm not sure that would be so good. Has anyone got a source of the clear poly tube ?
Thanks Rob