I've been using translucent polyurethane tubing to run my B100. It's been holding up well for the past year now, while other hose I bought new at the auto parts store has begun to degrade. It also allows me to see if there is any air in the lines.

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1987 Mercedes 300D ~200K (Greasecar & Biodiesel)
1993 Ford F-250 7.3 IDI diesel 165K (Biodiesel)
1996 Thomas/International Bus with DT466 engine