I replaced a fresh water tank that had a bunch of screws under it. A whole handful. The little ones that are used in the hinges on cabinet doors.
Seen a few that have shifted and cracked a fitting.
Does your water pump cycle on when no faucets are open? That would indicate the leak is after the pump.
With the tank empty and on city water supply there’s no leak?
Getting under the tank can be difficult when it goes in first and gets an RV built around it.
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