I found that my similar problem was a result of not opening the low point drains. I now open them when beginning in the spring, once again mid season, and lastly at closing. Pool chlorine is calcium hypochlorite and much stronger - about 10 times more. I dissolve a teaspoon in a gallon of water and pour it in the fresh water tank twice. I then fill the tank full. Let it sit for 24 hours. Then run pump until I smell strong chlorine on both hot and cold at all outlets. Wait 24 hours and repeat. Drain everything, refill fresh water tank full and repeat 2 times to purge.
2011 Chevy 1500 SB 4x4 5.3L w/trailer tow
2013 Zinger ZT23FB
Reese Weight Dist. w/friction sway control