Ballast under the stand?

[GreenSpottedPuffer]

I just realized that I have never kept a ballast under the stand before. I have it in a spot that it really can't get wet but of course there will be a lot of condensation/humidity under the stand. The stand is quite solid with just a few spots for air to escape.

How does this effect a ballast?

If it makes any difference its a PFO dual 400 watt. The ones in the big silver box.