Thank you for that.
It has no numbers (not digital one I guess?), just a dial that turns clockwise up to 'boost', but I can never get anywhere near that.
I have to turn it down until it starts, then gradually build up the speed but it normally cuts out (red light comes on) before I have enough flow to thoroughly clean.

Even the older version has a cut-off setting does it not? Never used the older one but isn't it a blue inner dial or something?
Just a black dial, no numbers at all!
Good news about the mounting of the pump, thank you.
Also, no kinks in the pipe... that was the first thing I checked and was hoping that would be the problem.
Sometimes I can build up the flow and it just keeps going no problem but mostly it wll only go so high then it cuts out and I have a hell of a job getting it up to the level I need again.
Sorry to bombard you with questions, I really do appreciate the suggestions.
Andy