Drew,
I do not know your budget or if this will be a one time thing but there are some special low lying fog machines on the market that use refrigeration to cool the fog, the downside is that they are thousands of dollars.
A cheaper alternative to this is a fog chiller that uses dry ice or regular ice. This is a link to a fog chiller that uses regular ice http://www.theatrefx.com/moreinfo_fog_cabin.html .
Now, here is what they do not want you to know... That $170 fog cabin they are selling is just a standard cooler with holes cut on each side for the fog to enter an exit. They have built a "cage" about 3" in the bottom to let the fog pass through under the ice. I have bought this cooler for a production and it works great but, I have also built my own and its very simple.
Your fog machine will have to be able to shoot the fog into the inlet of the chiller, so using the fazer with a wide output will probably not work. As far as the fog juice from froggys, the freezin fog is formulated to be thicker for ground fog however, when the fog begins to warm back up, it will start to rise and leave you with a heavy fog in the air. If you want your ground fog to dissipate as it begins to rise, go with their fast dissipating formula.
Here is a link on how to build your own cooler. http://www.gotfog.com/fog_machine_chiller.html