Mawaan moves the butt
Here's a brief description of the contestant's attempt. Someone's probably working writing up more detail!
Mawaan tried to stop the water leaking whilst putting more water into butt A with a hosepipe. As he moved butt A, he accidentally knocked it over before he and Alex balanced it against butt B. He connected the hose to the hole in the bottom, so the water was still being transferred from butt A to butt B. He moved 16 inches of water into butt B.
(Written by Taskmaster Wiki contributors)