Wookey

sorry coded in MATLAB - can port to GNU Octave Forge and possibly C or Java. Just thinking about the best tank visualisation methods. This is of course just a bit of flash front end - the big job is the tank model. At present I have 100 slices in the tank and based on State Space theory

http://en.wikipedia.org/wiki/State_space_%28controls%29but that may not be up to the task. The mass flow terms are a major challenge also how far unmeasured states to the tank can be inferred from measured outputs. This might work (or not?)

http://en.wikipedia.org/wiki/Observability And of course there is

http://en.wikipedia.org/wiki/Kalman_filterCan we tell our pump is in without a sensor - infer water rates etc?

Wouldn't attempt any of this without MATLAB/ Octave forge - unless anyone else is going to suggest something better? These are proper algorithms - dare I say real computing - not this database flimflam!