Water tank ballooning?

Campwme wrote:
Last night we heard very loud noise that literally rocked our 2000 Class A Dolphin National 37'. Took the flashlight looked all around, up and down, over and all. Nothing. During the night heard several loud popping noises, everything works fine. This morning when I got up put my feet on the floor I almost fell forward, thought I'd lost my balance,,hmmm. Went into bathroom came back into bedroom and literally walked uphill toward the bed! What the heck is going on? Woke up the hubby, went outside exploring in daylight, nothing looks unusual but then upon opening the very last basement doors on both sides and using a flashlight, voila! The water tank is literally ballooning and pushing up the floor! Shut the water off from outside, turned on faucets inside to let some out. Question is, will the tank go back to normal size?

it should regain its form but never ever seen a water thank not have a overflow hose relief system and also never seen where city water flowed through a holding tank before tap deliver; mine is city or tank water on a lever if I leave it on tank the tank over fills and drains out on the ground so there something really screwed up here for sure