As I've been getting more "experienced", I have sometimes had a bit of difficulty recalling the exact capacities of of our T@B's holding tanks. Since it can be very handy at times to know how many gallons each tank holds, I came up with a few pnemonic tricks, that I thought I'd share here..
I think the chart is self explanatory, but to explain how it evolved, the first thing I realized was how the numbers added up. But, it was only after I realized how the tank names were in alphabetical order, that I could be sure which one was which. The color reference, like mixing paint, was more of an afterthought, but it reinforces the alpha order representation of the math equation.
Granted, these tank sizes may be different in various models, but they do apply to many of the 320 model years, so maybe you'll also find this helpful.