For the Gas, change the food to a premium food. They will consume less since it's they have no fillers and the "end" result will improve. I use Orejin/Acana or Fromm but here's a link for you.
http://www.dogfoodanalysis.com/dog_food_reviews/
Try to stay above 4 stars, I know it sounds silly but it really improves the gas issues. I tend to stay away from the box stores for the pet foods as most of them have been too commercialized and have grain in them etc. Some are still ok. Water bottles for discipline couches etc.