On Jan 13, 8:46 pm, "john brook" wrote:
It was only a few years ago we bought an expensive Ikea sprung double
mattress and its now no longer flat but has hills and valleys. Also it so
heavy that its almost impossible for us to move about for spring cleaning.

I've had a waterbed for 20 years. The hills and valleys smooth out in
a few seconds!
It's impossible to move as it weighs 300kg, so if I move it to another
room I just drain it and refill with a dollar's worth of water.