Currently the mod doesn't show fluid contained inside fluid wagons, is this planned on being added?
Each wagon contains 3 tanks that can hold 25k of a fluid. By default all 3 tanks in a wagon are connected but can have up to 4 different configurations. At maximum (all separated) each wagon could potentially have 3 different fluids.
I currently have my fluid trains set up like my item trains, 3 wagons, 2 engines on each end. 25,000 fluid x 3 tanks x 3 cars = 225,000 fluid max of one type.