Deep well in 2000 when 1st htr was installed,cut over from a shallow that was here for 200 years.....Never a problem in our 50 yrs here till.....

In 2006,2000 htr rplcd,6 yrs old, leaking from under jacket,AO freebie,warranty.
06 one just crapped out last week leaking from the rod nut.....couldnt get it out,tried breaker bar ect...no impact wrench(should a looked here 1st and rented one).....so.....replaced this one.385.00 out a pocket and 100.00 to instal.
Any how looked in the old and the rod was disolved completly and I guess corrosion started working on the hex nut and threads causing the slow leak and locked it in......

Soooooo heres the ???'s.....
1# What is and should I or can I fix the water prob and not inspect the rod or..
2# just inspect/rplc rod yearly.....Heaters cost to much,but will the rod on this Rheem come out in a year?
Also should the rod be loosened now as its new and taped or treated with anti-sieze our what ever to make it easier when replacement time comes in a year or will yearly make much easier to get out?
Thanks in advance.