Suitcase, I use neoprene inside the tank with a stiffener so the clunk stays free but to the rear of the tank just like Wayne and the others have mentioned. I use tygon on the outside of the tank for visual purposes. I barb everything and use small wire ties on all fittings. It works very well for me. Zero problems with leaks or lines falling off etc.....[8D]....Bill Knock on Wood....