Hello: The only function of an anode is to stop rusting in a glass lined steel tank. If there is no anode, the tank rusts.
Removing the jacket isn’t too difficult if the tank can be rolled around. You remove the top and bottom if possible and then cut the metal jacked down one side. If you’re lucky, the jacket will peel off easily 😎 You may need to get creative a tanks are not all assembled in the same way.