PVC hose is a horrible choice for any installation on the boat. If you care for my advice - don't do it at all. It is inflexible, very hard to get on any fittings and absolutely impossible to get off. What more - it gets permeated too, no matter what anyone says. The problem is - because the damn thing is so hard to work with - you will leave it where it is until the smell gets completely unbearable or you sell the boat, whichever comes first. Moreover, because it is so rigid, it forms much worse seals on fittings and stench will come out of those seals as well.
Use flexible hose (shields 101 or other similar odor-safe rubber flexible hose) - and it won't get permeated any worse. But if it will - you can actually take it off, and replace, or (gasp) adjust fittings - what a concept!