For the last two weeks my ferret has had diarrhea every time he goes to the bathroom. I took him to the vet today and after testing a stool sample the vet said they couldn't find anything that could be causing this. The color is normal it just seems to be watery. Does anyone have experience with this? Any suggestions? I was planning on changing his food to see if that helps but he's been on the same food since I got him so I'm not sure that will help much. 

Any help/suggestions would be appreciated!

What food is he on right now?

Right now I'm feeding him zupreem. 

How old is your fuzz?  Is he eating and drinking ok?  A stool sample can check for parasites and certain organisms but not viruses.  Ferrets can get the flu.  Has anyone in the house been sick?   
If it's something like inflammatory/irritable bowel disease (IBD) the vet may have to do a biopsy (sample) from the intestine to determine what bacteria is causing it so he can prescribe the right antibiotic.   I'm currently in the same situation with Alice.  We feed Zupreem as part of a mix.  We have 9 ferrets and none of the others have had diarrhea.

THE DOOKS OF HAZARD