Hello. Thought I would share this in case anyone else has a GSD with dicky tummy. I have a rescued GSD called Heidi. At one time, she had the usual GSD wobbly stomach, every few weeks she was sick and had Montezuma’s revenge. The vet treated her each time, but didn't come up with any reason for this. A year ago I had a new boiler installed with all new pipes and I found that the water tasted a bit funny, so I started boiling Heidi’s and my drinking water. The thing is that since I have been boiling the water (and I’m crossing my fingers here and touching wood) she has only had one very small blip with her stomach over the past year. I wonder if tap water had something in it that was upsetting her. Obviously this might just be an isolated incident, but if you have the same problem it might be worth a shot. Best wishes for the new year from Carol and Heidi (woof) x