If you are parked in a southern area green mold grows INSIDE the hose.
Yes, I was very shocked to find this out after my first long term stay in Florida. I took the hose off to fill a bucket and noticed very tiny small green specs.
I asked the owner of where I was parked what this was and she said yes green mold builds up inside water hoses!
I cut my RV hose in half and the whole hose lining of the hose was covered with green mold! :E
And it did have an odor so I would assume it would also have a bad taste.
During my long term stay there as a precaution I replaced the hose every month.
One of many reasons I do NOT ever drink the water in the RV. :W