Say I have a controller of type ‘Trigger: Timer (Daily Point)’ that opens a valve (e.g. to fill a tank at 6 a.m. for 1 hour).
Say I have another controller that deactivate the first one on some condition (e.g. tank full).
What happens?
Outside the trigger daily point and duration, this controller is deactivated and the tank won’t fill
Inside the trigger daily point and duration, say at 6:30 a.m., does the valve remains open or does it close?
The best way to figure out what would happen in a particular scenario is just to test it out, set up a conditional controller, add the necessary inputs/outputs, and just see what happens with different conditions/actions in different scenarios. That’s part of the fun, isn’t it 
A conditional controller could be added via Setup>Function.
The concept would be for the controller to trigger an action/output if the current time is between 6-7 am+ the water level is within desired range, based on input measurement from let’s say distance sensor. A great starting point would be the Functions page in Mycodo Wiki - Functions - Mycodo