The answer is almost all cases is no.
All of the AromaTech diffusers, except the AromaCube, have a wire mesh filter in the oil pickup tube.
Often it's over looked during the initial setup, and noticed during cleaning or troubleshooting of the diffuser. Rest assured that it's completely normal and this actually is helpful for your diffuser and is indeed intended to be there. If you have any additional questions about this or anything else please email our support department at help@aromatechscent.com.
Please see this image for an example of the mesh filter