Help me decipher atopic dermatitus clues? it's relentless!

ok, I know a lot about my pugs allergies and atopic dermatitus. But his environmental allergies have cropped up and I've been trying for 9 mths to get relief!

He's 8 yrs old. As a pup we found out he's got food allergies. Simple. No beef/lamb/chicken, eats only duck or fish (or buffalo). Done. 8 yrs never a problem.

But 9 mths ago it cropped up again. Last July, a few weeks after I moved into a new apartment (I think this might be the clue) his skin broke out, etc. I took him to vet for some antibiotics. Cleared it up. Come November/Dec, he breaks out AGAIN. So in Feb I took him to the vet AGAIN and dropped down $250 in antibiotics, anti itch, etc. A months worth of antibiotics and it cleared up and now a few weeks since he finished meds it's all cropped up again! He is miserable and I'm miserable looking into his desperate eyes that tell me "I'm so unhappy make this STOP!"

btw, yes of course I tried antihistimine/benadryl. Nothing. I wipe his face/ear folds regularly. I'll admit up until now I haven't tried antibacterial/antifungal medicated wipes. I always used baby wipes (for 8 yrs) and we were fine. I've ordered some.

But I think it may be this apartment. Basically, this is a brand new building, my apart is new. But we have this eco-conscious air/heating system that's basically 'recycled air' its supposed to be energy efficient (lower energy bills, better for environment, blah blah) BUT tons of residents have complained about it, unmanageable temps (it'll skyrocket to 80' in the middle of the summer), smell of cigarettes/pot coming from air vents (this is non smoking building), sinus/skin problems. These are people complaining. For me, I don't seem to be effected. My apartment never smells but I'm wondering (and FYI, I bumped my head in a serious accident years back and it damaged my sense of taste/smell so I can't even smell coffee brewing or perfume if I sprayed it in my nose) MAYBE Larry dog is effected by this negative air even though I can't sense it?

I don't know! But another vet visit? And clearly antibiotics aren't working! $250 worth didn't work!

-maybe I need to start a food test again? Start all over? in addition to duck/potato/fish I do throw him some veggies, cheese and peanut butter, maybe he's suddenly developed a allergy to those?
- get serious w/ the antifungal/antibacterial wipes and scrap teh baby wipes?
-natural remedies? Fish oil, apple cider vinegar?

throw me some clues, is it possible to develop new allergies later in life?