Pulled the anode on the bargain water heater, only about 24" tall, aluminim, .700 diameter. Changed to a 48" for 13$, .900 magnesium.
Removed the POS "drain" valve, which broke apart in the process and added a ballvalve. Now its a 700$ water heater.
Went to change a 7 year old drain valve [plastic] on another heater, Shattered on the first part of a gentle turn. after digging that junk out, got about 2 gallons of calcium out of the rig with a dowel and the water running slowly.
The guy that starts a water heater tune up campaign would make a lot of money and really help people save their existing machines.
I was crushing some water heaters with a backhoe recently for the scrap yard. New ones flattened out like tin cans. Older ones took some work. Galvanized well tanks can only be punched in a bit in the center. No wonder they lasted 50 years.