H'mm, this is an odd one.
Have you tried going back to city water since using the pump and does everything now still work on city water?
Reasoning of my thought is "something" was partly clogged in the pump line. The clog was not an issue on city water originally. But now that you are pumping from the fresh tank that clog moved and plugged a path to the other water fixtures.
I know this is a long shot, but is about the only thing right now I can think of that would do this. That is if your piping is still all Sunline original. Technically someone can install check valves to do what is occurring, but why? would be a really good question.
Let us know what comes from this.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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