I'm not sure how/why you can use a rig a lot and not use/need hot water.
That being said, you source for water is apparently very dirty/cloudy. I would suggest you purchase an inline water filter............Camping World stores have a variety. Also, check your on-board water filter for if/when you use on-board water for dry camping/boondocking. Even a small screw on in line filter on the end of your water hose should be looked at and/or replaced. Changing the anode is only required when the component deteriorates due to bad water sources.
Ken and Terry
2010 Georgetown 330TS being pushed by our
2017 GMC Terrain toad (4 wheels down)