Oils for reed diffusers? I'd like to trade name my own reed diffuser. I looked at...

I'd like to trade name my own reed diffuser. I looked at the reed diffuser questions on here, but none of them really talk about the grease. All I want to know is, is there a specific fragrance grease that I need within order for this to work? Could I use, say aloud, Bath and Body Works fragrant oil? Or The Body Shop grease made for oil warmers? Or does it enjoy to be actual "diffuser oil"? I've heard that essential oil are best because of the therapeutic benefit. However, they're more expensive largely, and I'm not interested in making this for the remedial benefit.
Any help would be great!
What will I have need of to build...
Answers:    Any sort of potpourri oil or essential grease would be OK. Pier 1 has a nice mixture of diffuser oils, also Bed, Bath and Beyond.