Thanks for this, i made a similar thing (although quite small scale) when i got my first sizeable order, it was inside a pig sty and so i was cutting lengths to 3m, i've now moved on and want to keep the lengths uncut if possible.
I've looked a various ideas, i liked the simplicity of using 4 or 6" plastic tubing but discovered it's fairly expensive. Reading your solution i guess there's no getting round the fact that it's going to cost me to set up decent storage. But i suppose it will last a very long time!