Ok so I almost have the wife talked into letting me put a used feed bin in her flower bed for corn storage. It is a metal 2.5 ton bin and comes with a flex auger. I got it for the cost of me removing it which works out to be about a case of beer for my two buddy's who helped. I figure it should hold about 100 bushels of corn. If I fill it up in the fall, say around the middle of Oct will I need to use some kind of aeration to keep the corn from drawing damp? I usual get corn from a friend and although I dont know the true moisture content it has to be low because I have no trouble burning or storing in my sealed wood bin in the basement. I just dont know how temp changes outside(hot one day cool the next
) will affect the corn in the metal bin. Any ideas?

if the corn was dry enough to store it in your basement bin it will be ok in a steel bin outside. Look at all the bins in the country that we store corn in. as long as it doesn't get wet you will be ok. I would be sure to empty it rather then hold corn over summer. Haul it to a grain elevator if you have to. Sometimes in the summers temp changes and higher humidity you could get weevils and end up with more problems.
I would make sure the corn is 15 % or less in moisture and is air temp before you fill the bin.

I figured it since it stored ok in the basement it should in the bin also. Just wasnt exactly sure why all the bins around here have the big fans running during harvest. I know they have grated floors the air is pushed through. I guess they do that so they can shell it at a little higher moister content? I now need to come up with a nice color paint to match the rest of the buildings. I was told NO to the galvanized look by the house. Thanks

Being in the painting business for many years I'll toss out a suggestion. if there is no rust and the galvanized is weathered (not new and shiny) you can paint latex over it without primer. This means you can match your house color pretty easy. If there is rust on it I would use Rustoleum Rusty Iron Primer as a first coat. I have done this with many buildings and never had a problem.