Agree with the rest. Ditch the brass plug and get the nylon type that came on it. The nylon is used to make sure there is no reaction between dissimilar metals. Of course there may not be any with brass and aluminum.
But the brass will damage the aluminum threads in the water heater if they get cross threaded. Nylon plug will not. Plug may get damaged cross threaded, but replacement is cheap.
Erroll and Mary Doss and Duffy (RIP)
2017 Jayco Jay Flight 23RB
2014 F150 SC, 4x4, HD Pkg, Sterling Gray