Nice pics, looks like it's going to be a great setup. Though tough to determine the pipe size... see if you can get a measuring stick in there and measure the inside diameter of the pipes... maybe 3/4" down and 2 x1/2" up but that seems wrong... 1" and 3/4" just seems more 'right'.

On the other note, a refuge would be a definate benefit... since it looks like you have room in the cabinet to add it... setting it up right while it's dry is the best time.... it helps keep the floor dry.