What's that smell?

[Got Water?]

I let the tank cycle for more than 2 months before adding anything, and then only a cleaning crew, I have only added 1 or 2 fish per month if that. I test for ammonia reg. and it has never gone over 0.25. I often think I'm not feeding enough because there is never any food left after 2-3 min. and I only feed twice a day. I have been fortunet not to have any deaths yet except for a jumper. The tank itself dosn't have a smell, just the refug. tank. I clean out the protein skimmer 1 or 2 times a week, and a pwc every 2 week. At this point I think it might just be the new cabinet and that it will go away with a little age. I hope!