Rockwood / Flagstaff to my knowledge still has woefully inadequate tank supports at least for the freshwater tank. The supports are actually a standard LCI part consisting of angle pieces made from bent plate. It's not a matter of if they will fail, it's when. You'll need to do something as Soundguy has done, or something such as this.
I added an additional tank for 80 gallons total capacity and made the supports from rolled angle. Not much larger than the Lippert garbage in size, but substantially stronger. 2017 Rockwood 23WS.
