? Anode "Nut" Question -- Anti-Freeze 'Stuff"?

Use a bathroom scum remover with acid in the mix like CLR. Put some on the threads and then work the pipe nipple like OB recommends, The acid will remove the scale and you should have bright threads. Reinstall with multiple wraps of teflon tape. You will still have metal contact between the anode and the tank. I'd recommend not to use Crisco because it contains salts and vegetable oil turns sour but may work reasonably well.