Dan,

 I've been using formic for about 15 years. Here's my method.

  I use D.O.T drug sample cups with lids. You drill a hole in the lid, cut a three inch piece of candle wick push it through and use a hot glue gun on the inside to seal the hole (leave some of the wick exposed on the inside) you should have about 2 3/4 sticking out. Put a knot at the end, then put a split shot fishing sinker at the end right above the knot, this will keep the plastic bottle from blowing off if its windy.There's one draw back to my method, we use the top feeder hole as the formic hole. In other words, you have to have a hole in your lid for this to work. Out here in Calif., most of us use a top style feeding system  I design this method around that. I fill about fifteen hundred 4oz. bottles in a day and put them on the next.The nice part about this method is you don't have to mess with the hive, just pop out the feeder plug and set the formic on. It normally takes about three weeks to a month to evaporate threw the wick. It is not a cure for the mites but just one in my arsenal.

 Good luck 
Keith Jarrett

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