Because there is some issue with handling the unit conversion, my suggestion is to just look at the number and ignore the unit. In other words, when setting the flow rate, just set the number to what you need (0.25), and keep the unit the default (I think it’s liter by default, which is international standard). This way, when you see a flow volume of 10, that is in 10 gallons, and ignore whatever unit it’s displayed with.