thanks Becky! One of the things I'm worried about is my barn is OPEN. I'm wondering if I should hang the nozzles ABOVE the rafters to keep the mist from blowing out of the barn. I noticed this morning that the flys seem to hang out up there at night. Right now, I have the hung under the rafters.Carin, if you find out about any other product besides the Pyranha for the 55 gal system, let me know.I love my system, but yes, the refill is pricey!However, it's the best thing I've used for flies in the barn. Fortunately here, I don't have to start mine until sometime in May and one fill will take me through the fly season.