(We neglected to replace the sacrificial magnesium anode rod (s) in a timely fashion.)
Any tips on filling up the grooves would be greatly appreciated.
UPDATE: I failed. AND I ruined the air filter in our HVAC system -- the flux-core welding wire produced so much smoke that it totally clogged up the filter (a 16x25x4 inch!!). I thought our capacitors in the heat pump had gone bad. (Actually, they had degraded below spec, but it was the clogged air filter that really put the damper (sorry -- I love puns) on the HVAC system in the middle of a cold winter.)
