What if the user wants to track two weeks of water?
Pull in the Clock component from the Sensors Drawer.
It has blocks to get today's date, and to convert among different formats.
Using tags like yyyyMMdd (20230615) would let you track water usage longer.
Once you have the current day's water usage, set the Enabled attribute of the Decrement button to (usage > 0). Repeat that check after each change of value.
AI2 has a Charts component. Read up on it and on AI2 lists for a fancy display.
You would have to keep a starting date separately, and use how many dates in from start as your x axis.