Playing with the device alarms a bit, I found the following:
For the MPS Pressure/Level Sensor and the MPS Flow Sensor, forcing an alarm situation caused a red bar to come up on the device alarm page, but nothing else was noticed.
I assume, but could not test, selecting the Speed Signal / Output option at the top would disable the Tacho/RPM signal at the back of the aquaero, giving system shut down as the only action option.
The Actual Alarm Level remained at zero and there was no further interaction with the aquaero Alarm Actions tab.
For the MPS D5 Pumps, forcing an alarm situation caused a red bar to come up on the device alarm page, AND Actual Alarm Level was set to 2, with the aquaero reacting by executing the alarm level 2 setting (red LED & cyclic buzzer)
Again, I assume, but could not test, selecting the Speed Signal / Output option at the top would disable the Tacho/RPM signal at the back of the aquaero, giving system shut down as an additional option.
Just my observations.