Thanks for the feedback everyone. The tubing I am using is the "by the foot" from Rona or Home Depot. The barrel is food grade so I don't think that is the issue and now that I think of it I switched to this food grade barrel because the same thing was happening with my old rubbermaid container. I am confident that it is the hose giving me the issue. The original hose was from an aquarium siphon & fill set I bought years ago but I have replaced it a few times because it tends to grow algae or mold or something undesirable in it over time - maybe because it's clear and light gets to it. Anyway I will look for a food grade replacement. It is so obvious that would be the answer it's no wonder I never thought of that.
Although I don't RV so I'm going to use that as my excuse.
Thanks again.