Suburban WH are the only ones that use an anode rod. Aftermarket sells anode rods for Atwood but they are not needed...Atwood doesn't supply them OEM.
Suburban is a steel tank that is glass-lined..hence the need for anode sacrificial rod...protect the steel tank (Atwood tank is Aluminum Alloy)
Aluminum rod lasts longer especially when water quality is good.
Aluminum can 'grow' deposits..calcium will collect on rod....just wire brush off.
Magnesium will deteriorate quicker than aluminum BUT can cause a sulfur smell due to reaction to microbes in water source.
As long as anode rod is deteriorating it is protecting the tank.
Faster deterioration doesn't mean it's working better...just deteriorating faster.
No need to change out until 75% of rod has deteriorated
