Anyone have an issue with the fresh water tank not holding the amount stated by Heartland? I have a 22 Heartland fuel 357. Heartland states it holds 100 gal. fresh water. First trip ran out of water. Sewer and grey were not full. Filled up again using a gal. gauge on the hose. Water started coming out the overflow at 69.6 gal. Over the course of 6 hrs I was able to fill to 78.7. Can not get anymore in.