Help...my doodle is vomitting almost every morning

[Amy & Cosmo]

My labradoodle has always had episodes of vomiting off and on. Usually he only throws up 1-2 times then is fine for awhile. He had an episode that lasted a couple of weeks in January and we took him to the vet weekly for three weeks. All tests were negative (blood work, fecal, no X-rays). He was given antibiotics and famotidine and the vet told us to change his food.
A little background on his food...he started on orijen when puppy and had bad gas and soft stools. We switched to acana and he did very well for almost a year. With the food shortage it became hard to obtain so we researched and ended up changing him to taste of the wild. He did very well on that but I was never comfortable with it given the recall history and being owned by diamond.
So, I'm December we switched it petway, a local grain free food. Since the vomiting and diarrhea started about 3 weeks later, our vet thought it may be food related. So, middle January we changed to orijen because it was available at our local pet store.
With meds and new food, his symptoms cleared. However, he began having the bad gas again and his stomach was making horrible rumbling noises at night and in morning. So we decided to check back into acana and found it is available online, so we started the switch about 1 week ago.
2 days later, the vomitting began. It is every morning around 4-5 am. No other symptoms. Stools good, energy good, appetite good.
So, do we keep trying the acana and see id symptoms clear. Do we switch back it taste of the wild. Do I just give famotidine at night ( that seems to really help). I don't want to mask symptoms but I don't want a series of ineffective vet visits.
Sorry for the long post, but I would love to know
If anyone has any insight.

[Donna K & Quincy]

Amy try feeding him something at night before he goes to bed. Some dogs seem to throw up if their stomach is really empty and a bedtime snack seems to help. What does he throw up? If it is just yellow bile looking stuff the snack will help.

[Bonnie and Kona]

That was going to be my suggestion too, BJ.

[Jane, Guinness and Murphy]

Both Murph and Guinness have a tendency to spit up bile first thing in the morning.  We give them a cookie (two for Murph) around 10:00 when we're heading for bed it seems to help.  It doesn't prevent it totally...but it does help. 

[Linda, Charlie Brown and Beau]

Yes, I think BG is right about some puppies needing a little something in the tummy at night.  Are you saying there is a shortage of Acana?  If it was just the fact, it is not available in your particular area, you could order it online, and subscribe to a monthly or bi-monthly subscription and even save on the price?  I do not see Petway on the good food list.  You might ask Karen in the Food Group what she things since she is the food guru.

[Karen, Jasper and Jackdoodle]

In order to determine if there is some particular ingredient that is causing these digestive issues, we would need the specific formulas and not just the brands of food. You might then see a pattern that would indicate a possible intolerance to a particular protein or ingredient. 

[Amy & Cosmo]

We tried the right before bed snack, and he still threw up. It is not just bile, but partially undigested food. The acana shortage is over, which is why we put him back on it.
The taste of the wild formulation was wild prairie, as is the acana we are currently using. The orijen was the adult formula ( not regional red).
We gave famotidine tonight with feeding ( he is fed twice daily about 10-12 hrs apart). I will see if this helps.