If you have an Atwood hotwater heater, you don't want to use an anode rod in it. You may need to flush and clean your hot water heater. First drain the hot water heater and then fill the hotwater heater with a bleach and water solution and let it heat up and then drain. Next use baking soda and water to fill the hot water heater and heat it back up and drain again. I use about a 1/3 cup of bleach in the solution for the heater and then about a half box (small box) of baking soda for that solution. You can fill through the pressure releaf valve opening. I also use an attachment that I bought from Camping World to flush out the water heater between the bleach solution and the baking soda solution. It will break free lots of the mineral deposits that builds up in the heater.
Hope this helps.
Dave and Karen -- '02 Ultimate Advantage 36 C, 350 HP Cummins, Allison 3060 Tranny
'07 Ford Escort, Brake Master 4160, '13 Ford Edge, InvisiBrake