09 3950 water tank storage issue

Ok, recently went to Zion for a nice trip and while filling the water tanks, the tube between the 2 water storage tanks (I believe there are 2 65 gallon tanks). I can’t seem to find a replacement hose (roughly 8-12” in length) but don’t know diameter. If anyone knows the size/diameter and type/material that would be awesome. I’m thinking I need to change it out.
 
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