honestly Yoe the best thing to do is just cut out the grains for a couple weeks and see if anything improves. Do starchy veggies like potatoes to replace the grains. It might not even be a matter of bacteria, you might just be sensitive to grains. There's alot of people like that out here! Certain grains are harder to break down than others. For example quinoa feels like it rips my gut apart but I'm fine with white rice. Potatoes are a wonderful superfood, one of the most nutritious foods there is. The only way you're going to know is by experimenting, unfortunately