Teardrops n Tiny Travel Trailers

Another thing a buddy of mine does with his alloy boat to stop her oxidising is earths it

He has a steel rod driven 3 feet into the ground and attaches a wire from his boat to the rod

He reckons it stops the white oxidising patches occuring, and he seems to be on the money as his 6 yr old hull looks as shiny as it did when he got it.

The grounding or "earthing" as you say makes some amount of sense due to electrolysis being a real and true force of nature. I fly and work with a bunch of vintage aircraft and they are never grounded electrically unless being fueled, modern aircraft are not raw aluminum vintage aircraft were non coated because the coatings did not adhere well back then and hid missing rivets or cracks. During WWII allied aircraft over Germany were polished of all camo paint in one night due to snow on the ground, snow made a green bomber really easy to see from above! We keep the aircraft shiny by always putting them in a hangar! With teardrops and old planes there are several factors to consider, humidity, temperature, salinity, PH, airpolution, hot and cold expansion, UV rays, ETC....Subway tracks are grounded in certain areas to avoid degradation of the metal by "stray" current and only gold or silver coins last in the ground from the Roman Empire all other metals were lost to electrolysis. Ships are now protected from corrosion with active current. I rambled on and on this time but I think there is definetly some science here and worth looking into!!!!

You might try this. Looks promising.
http://www.sharkhide.com/

Get yourself a Cyclopro 5 and mothers polish. Works like a champ.