DIY - How to build a hillbilly / redneck hot tub

How to build a hilly billy hot tub for under £50. The IBC container cost me £40, gas cylinder and pallets were free scrap, the only other thing I bought was a can of black spray paint and a couple of plumbing connectors. The copper pipe I had laying in the garage. All done in a massive rush for a garden party as one of my friends said it couldnt be done. Proved them wrong. :)