Hello Jon T. We have recently had some discussion about gastro-oesophageal reflux and this thread can be found here
There is another one here.
Opinion varies about protein levels but what counts most is digestible protein rather than the figures. Dogs find it easier to digest animal protein. The figures in dog food include the protein derived from other ingredients. Some dogs can cope with high protein, particularly if they are working, young or very energetic. Others cannot and sometimes anecdotal evidence points to dogs having loose stools when given high quality, high protein dry food. In all fairness, this could be due in part to over feeding because the RDA of these types of products may need to be lower than advised on the packet.
Gastro-oesophageal reflux is a complex problem and often needs some investigations to discover the cause. As a first step, it is useful to feed three or four small meals a day and to make sure the dog rests after eating. Feed the best quality food you can afford and if it is extruded kibble then it may be worth trying soaking it first because it might aid digestion. Dry food causes dehydration and it takes some time to break down in the stomach. Most pet owners will have seen their dog vomit some hours after a meal and if kibble has been fed, it may still be recognisable as such.
You have a young dog who is presumably active so unless your vet specifically advises it I would not be inclined to feed a low protein food in the hope that it will counteract the reflux. By low protein I mean sub 24%.
It might be that your dog has intolerance of one ingredient or another and if you suspect this you might want to consider an elimination diet. We have information about this on the forum. If you are a member of Facebook, consider having a look at the video on reflux that was recently aired on the My Pet Nutritionist page.