If you're "Z"ing a hose. so to speak, use a length of rectangular tubing for the vertical bit. Round the ends off to match the round tubes, or even use 1" X 2" rect. for 1 1/2" round and have a nice round end on the rect. that's bigger than the round stuff, so the hoses aren't sticking out past the "Z" bit. Not much more work, but a whole lot better looking!
By the way, you do know that the fan mount is inverted in your pics?