()-HOB

Good morning My name is Robert and I just registered. I live just outside Chicago and purchased this HOB from Glass Aquatics. I assembled it with no problem accept I somewhat confused when I opened the box inside the adjusting pipe was a large white rubber tube with an ID of 3/8; does this stay in the adjusting pipe; 2ndly part e2: Valve(sorry your parts sheet call v2:Valve) a little confusing; what does this connect to?; there was no tube with the product that would attach to the Drain Plug extending from the Collection cup.What connects too the 2 barbs coming off the Valve? and what size tube due I need to have? and should it have been with the parts.... Thank you for responding....Bob stay safe and healthy.