I did buy the bulb at walgreens, I found that I could not set under it for long periods when reading, It would make my shoulders hurt and made me feel like I was getting weak so I moved it under my house where its on 24-7 and It did help with the smell under the house. I had it in the kitchen and it dosen't get rid of bacon smell. I doubt if I'd buy another one. You have no way to tell if it's working a meter to test for pos ions is very costly