My water pump on the camper was running a long time to pressure up. Then just minimal flow and taking a long time to rebuild pressure. I was fearing a leak, but no water anywhere.

This is quick check solved the problem. Make this part of your semiannual maintenance, check the strainer/filter. Three GOOD videos below on various Shurflo issues.

"RV Failed Water Pump Check Valve is Leaking and is Filling the Fresh Water Storage Tank Part #1"    • RV Failed Water Pump Check Valve is L...  

"Preventing backflow of water into the fresh water tank when connected to City Water"
   • RV Shurflo Water Pump Check Valve Fai...  

Here is a very good video too of low pressure issues with a Shurflo water pump I highly recommend. :)
   • Fixing Your Escape Trailer's Water Pu...