I would think the plugin style would be much better then any spray or candle type. I don't use any in my frogroom. I would highly recommend finding a reasonably priced home air purification unit and running that. They normally have some sort of carbon filter as well to remove oder another suggestion would be an ozone generator. They can normally be purchased quite reasonably. This will also create much more of a rainforest atmosphere and smell. I have used both but currently have a nice air purification unit and it works great. I keep it close to my fruit fly shelf and I have to get my nose right to a lid just to faintly smell anything.