There are so many custom grains out there, we can't add them all to the list. In fact we try to keep the list as uncluttered as possible. The system has two options for taking care of the scenario where a grain is not in the list. A) Click 'add custom' in the fermentables section and fill in the name, lovibond and ppg for the ingredient. B) if you are planning on working with this grain in the future, a more permanent option is to go under Inventory, and add this grain as a 'Custom Fermentable'. It will then appear at the top of the drop down on the recipe editor. Down the road, we are planning to update the grain section so there is the default list, plus a community list that anybody can contribute to.