?B?4oCTIENvbG9uZWwg4oCT?= wrote in
news:2006012120225675249-nobody@verizonnet:

Yes, they do. I just replaced the anode in my natural gas water heater
today. Flat top on hexnut, so used an aluminum anode.

On 2006-01-19 20:08:33 -0500, "Bob" said:

You shouldn't run a water heater without and anode rod. It's there so
it can corrode faster than the tank. When it's totally depleted or
removed, the exposed metal parts of the tank corrode much faster.
Water heaters usually come with a magnesium anode rod and sulfur in
the water sometimes causes an offensive odor. You need a rod made of
a less active metal like aluminum or zinc. If you tried one and still
had the smell, then try the other one.

I don't mean to hijack the thread, but just out of curiosity, do *GAS*
hot water heaters have sacrificial anodes in them to prevent
corrosion, as well? Or just electric? (It seems as though it shouldn't
matter...they're both going to corrode.)