What is the procedure for replacing the anode that is screwed into the top of an electric hot water tank? In theory it's supposed to be easily replaced, but in real life getting any fitting unscrewed after many years can be a risky. Any tricks or just brute strength? I haven't change it. I suspect the cold water has to be turned off eliminating incoming pressure, but should I also turn off the breakers (electric heater) and drain some of the water out of the tank to further reduce the pressure or just use the TPR valve? Is the aluminum rod recommended to eliminate oder? Appreciate any guidance/advice
Doer

Yep, release the pressure and incoming water as well as electric. Use the correct sized wrench on the anode "nut" not just a crescent wrench. Brute force is nice but too much and you can start to rotate the entire tank screwing up you in/out lines. Have two burley friends hug and hold the tank if you're a big brute. Mag or alum are common and it can depend on the qualty of your water. Might ask a good local plumber what he installs. You will need to flush your tanks a few times if you want to get rid of the smell, you are holding 40+ gal of stink at present.

Go squirt some pentrating oil on it now. It may actually work its way in and do some good when you get to the job. Since the tank is glass lined, I would skip my usual hammering or heating with a torch. I would use the proper size 6 point socket and a long bar.

Use the bottom drain, not the TPR. They have metal to metal seats and often leak once opened and the least little dirt gets in.

The anode rod is a magnesium rod that is designed as a sacrifice metal to combat electrolosis. It is difficult to remove and you must use a 6 point socket.