I have all the respect in the world for Brian, but I don't see the need to put a 6' Nile monitor in a 5'6" tub for feeding purposes. Especially when it is recommended that monitors have a cage twice their length. I wouldn't want to move a possibly still hungry 6' Nile that could rip your finger off, I don't even like messing with Niles half that size. Or upset the monitors stomach and have it regurgitate.
About 4:30 in on this video= YouTube - SnakeBytesTV- Our diggs and a huge Monitor lizard feeding!!!
I don't suppose you saw where that particular monitor was kept as a 'non feeding' cage?