Now, found heaps of threads with similar question but with the tank ON the bike (mostly for winter hibernation).
I've got a slightly different issue.

got an extra tank I need to safely store. It has efi fuel pump removed so it has hole underneath & its not on the bike.
Any suggestions to protect the internals of the tank please? Filling it w gas doesn't look like it can be an option.
thanks guys.

 

Had the original tank and both fenders for my Xbones sitting on top of the bookcase in my office in Malaysia for 5 years when I had another set repainted to use on the bike. Lived on an island, so not only damp and warm but also salty air. Did nothing special too it. Parts were wrapped in an old towel. Still in perfect condition when sold with the bike.

Don't know if with the cost saving stuff they still paint/coat the inside of the tanks though.

If you worry about it, you could apply a film of oil or a product like CorrosionX that forms a very thin layer over the surface.

 

bringing int inside with the layer of protective spray makes sense to me! Could be a an interesting display piece too. Once protected I might tape the hole and shut the cap. Or would it be better to let it ventilate?
Interested to know if there are product designed specifically designed for it and will resolve away when I clean it out with the petrol.
thanks again.
Is there a