The vomitus has eruptedus.....again.....

Well, it's been over a month now that Walter has been on his 'holistic' diet. I have found that he really enjoys his Acana Grasslands dry (although it is insanely high in calories and thus has gained over a pound!) and he seems to have preferred the Snappy Tom and Almo Naturals cans (seafood only, no chicken). He was doing so well up until about a week ago and KAZAAM! The vomitus has eruptedus. Ugh.....just to be on the safe side, we treated him with an antibiotic for 5 days, to see it if was a bit of gastritis, but to no avail, the vomiting has ensued, though it seems to only be limited to the canned food, stupid allergies....
So, here we go again....onto plan A, version 2.0
Because I still don't want to have to medicate him with steroids (stubborn, I know), I have found a few cans of 'holistic' food that are duck and venison based that he likes (Natural Balance). So, I will try to keep him on this, as well as a bit of dry and see where this may take us in the next few weeks. If this STILL doesn't help (because cleaning up piles of undigested canned food vomit is on my favorite things to do list) Walter and I will be off to a colleagues clinic who practices both western and eastern medicine to see if possibly some Chinese herbs and acupuncture will help.
Until then, keep your fingers and paws crossed.