Try and tune this loop.

The controller controls a valve which fills the tank. Other users are trying to empty it. Your mission, if you choose to accept it, is to tune the controller. Caution the fluid is dangerous and spillages will not be considered kindly by the EPA.

Good luck!!!

 
Process variable trend
PV
Time axis

Please send your tuning constants to TUNING so we can try your values and perhaps comment on them. Write "Tuning" in the subject line.