Commercial beekeepers are using a aluminum Pepsi or coke (soda pop syrup ) container and drilling out the two holes and using a tap. In one hole they install a hose with a spray wand and the other a tire valve stem. Air up to 60 pounds of pressure and apply the oxalic. I was given a tank by a beekeeper north of me quite awhile ago but have never got around to making the setup up. I think it would take practice to get the measure right. We did not like the ivomec sprayer as too hard on the hand and the regular sprayer pumped too slow. Actually the syringes like Bill uses worked for us in late fall when the bees are clustered. I would point out: I really think that as long as the mix is right the 50 ml. rule is negotiable and we go by number of bees in the hive. It seems if I remember correctly at first it was 35 ml per hive. 50 ml. being I guess the highest amount you can use on a hive without some brood or bee kill. Dribble or stream is essential as spraying wood is useless. To *kill* varroa they have to be in contact with the chemical. Commercial beekeepers getting poor results *in my opinion* are not taking the time to apply correctly. bob *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html Guidelines for posting to BEE-L can be found at: http://honeybeeworld.com/bee-l/guidelines.htm