We are planning another Blacklight Presentation at our church and I want to use some Fog with some handheld UV lights.  I don't want to use UV Fog necessarily because I don't want to take the chance the puppeteers will be "seen."  Will regular fog show up enough?  It does not need to cover an area, just highlight the light. 

Don't really know the answer, but isn't fog basically a white cloud? So it should appear well under black light since white comes up well in general under UV. Don't know how well it would work in terms of keep performers hidden though. I guess it would depend on how much fog is pumped out at once.

I think Na may be right. I've never used it in a black light production but have seen it in theater productions that use UV and it seems to enhance it quite a bit. Of course they have been using other standard lighting also so not sure how much of that effected everything.

Did some poking around on the haunt sites and seems they conclusion there is that there is not such thing as UV Fog and those who say they have gotten it by adding something to the juice may be damaging the machine.  They do get cool glow effects by adding color light below the fog like rope lights since the fog reflects the color of the lights really well.  I think that may actually be the effect I am seeing on stages that I mentioned above.

Perhaps you could use some cutout shapes made of foam core board or something equally light that are painted with some fluorescent paint in the background behind the fog. That way, the black lights would cause any portion of those that aren't sufficiently covered by the fog to glow, and that glow would then be diffused by the fog. The diffused color would possibly make it look like the fog itself is colored.

You could just use white, or with several different colors you could have a multi-color effect, assuming the whole concept works at all.

We never mixed a fogger with UV when I did black light, but I think the best thing to do would be to use a directional light(s) with coloured gels and aim them away from the performers. If such a thing as UV fog exists, it would not be a good idea because anything able to make fog fluorescent is likely to make the performers' clothes glow as well.

Hmm, on second reading: why not use a 'light curtain'?
http://www.schoolofpuppetry.com.au/tutorials.php/what-is-a-light-curtain?tempskin=2013tutorials

We used this quite a lot doing puppetry in combination with fog and it was very effective. The direction and use of the lights kept the performers hidden but still allowed the use of fog plus puppets being seen in the relevant area of the stage. You might be able to combine it with some UV lights, if sufficiently focused on the right area. (I think)

Andrew made a great point... we used "blocklight" bubbles for a while at our old theater and over the course of a few weeks it became a catastrophe.... everything was pre-coated with it and when the blacklights lit it looked like a murder scene... we had to demolish the set and build a new one...and replace the stage carpet... i can only imagine what a floating fog would do to the puppets...puppeteers...and room.

I might add that it never really added anything to the look of the bubbles under blacklight except make them look a little yellowish... the bubbles actually showed up as well if not better without the formula added to the juice. If you are using the pro LED blacklights... they tend to put out a fairly bright glow that i bet would be enough to make your fog visable... atleast in the immediate area of the lights.

Thanks to all.  I am thinking that placement of any light is going to be the key here.  I'm not planning on using uv fog or bubbles because of the "murder scene" effect   That is what I thought it would do.  It is for a very small space above the puppeteers head so hopefully we can get positioned right.  Thanks!!

I think most of the UV bubbles and fog (did we ever figure out if UV fog exists?) is designed for use in nightclubs, "glow in the dark" bowling alleys and venues where you have UV light and regular light mixing.

Just FYI while we're on the subject, even regular bubbles and black light are a bad mix. The phosphate in most soaps/bubble liquid will glow purple/blue under black light. For the same reason, black light clothes should never be washed in detergent (I never had much luck with phosphate free detergent, but that was years ago and there may be better products on the market today).