I have made tremendous progress and then hit another block. The good news is that I think I figured out what is wrong and what needs to be done to fix it. I do still need to learn how to fix it and actually do that.
I have solved the calibration process by putting it into its own function that only calls during startup when a button is pressed. It occured to me that calibration can only be performed with a full tank, so it should be a little harder to get to. I have also set up a vertical menu structure that allows the user to select which tank they want to calibrate since they may not all need to be calibrated together. I also assigned char strings so that the tanks will display a value that makes sense to the user. This is where my problems started. Whith all of the additional bytes being used in SRAM, I ran out pretty quickly and it was causing the system to not boot with certian functions being performed. I ran some tests and confirmed this was going on.
Some more research makes it seem that by using PROGMEM I may be able to clean this up quite a bit. I ran out of time before I could make that happen. I did also play with an ethernet sheild and find it was pretty easy to use. It was exciting to think this may be fairly easy to send the data to a web database. That makes this a very powerful tool.