[nanomonkey]

My first suggestion would be to cook it longer than 22 minutes. Instapots only go up to around 9 lbs of pressure on high, from what I read, so any pressure cooking recipe that is expecting a 10-15 lb pressure stove top cooker will need some extra time added. I cook my pintos and red beans for 30 minutes.

I would add a 1/4 teaspoon of baking soda to the water. I don't reuse my soak water, and I don't salt my water until after they have cooked. I may experiment with adding salt beforehand later, but I suspect that I'll need to add salt to the soak water too for this method.

Adding garlic and bay leafs are nice, but not necessary, as is an onion. For red beans I often blacken an onion on the stove and then throw it in whole in the pot with the beans.