Oxalic Fogger ?

I use it for Oxalic Acid. Minor issues in operation come down to ensuring you thoroughly clean between use or it clogs up machine. Pump water through it cold until clear then store with water in lines.

Issues of effectiveness come down to ease of obtaining grain alcohol. If you're not in an area where you can purchase at a local outlet then you're apt to use a cheap vodka. 80 proof will work in the heat of the summer and not storing mixture. Use in the same hot afternoon you mixed it. OA will precipitate from water heavy solutions in cooler temperatures. Pure grain (190 proof) alcohol is the only way to hold enough concentration of solution on cool mornings and store mixture between uses. 100 proof will clog your machine if you attempt to use it on a 50 F morning.

The concentration is the saturation limit. You'll not be able to add more than 25 grams of OA to 100 ml hence the screening of solution after mixting being in directions. There will be some precipitate due to saturation limit of solution. Units to mix for Americans is 2 Tablespoons OA to 1/2 cup grain alcohol.

Thanks for your response. I have seen recipes that use distilled water and mineral oil with the Ox...not sure what the secret is in using grain alcohol.(other than your explanation about temperature etc.) Where do you obtain grain alcohol ? Vt. Liquor stores ? And, does it do the trick ? I have been using the OX vaporizer and it takes some time to treat all the hives...and also pisses off the bees. I have also used the Swedish Sponge method but perhaps had too high of a mite count at the onset. It is a never ending battle.
Also, I assume you have to heat up the alcohol/OX solution to dissolve properly ? Have you considered trying the Glycerine/OX mixture in the fogger ? Would have to be heated and cleared. That is the recipe for the Sponge method.
Thanks again, Peter