Yes! Each type of Fill it Forward Tag has a unique barcode that allows the app to differentiate between the reusables being used.
If you would like to track more than one reusable within your Fill it Forward App user account, please use a different type of Fill it Forward Tag for each bottle/cup/bag/container. This will allow the app to recognize the unique barcode, and track your resuses as being separate.
If you are using the same color Fill it Forward Tag on multiple bottles, you can only track one size (oz/ml).