I'm going to build a mechanism (as simple as possible) like the ballcock system used in flush toilet. But mine should be able to continuously discharge and refill automatically.
I already have a draft idea how to do it: referring to a classical ballcock system I would remove the handle and connect the lift arm to the flush valve flapper. In this way when the float reach the fill position will automatically trigger the discharge.
Before reinvent the wheel from scratch I wonder if this system has a specific name so I can find other resources or even products.
The goal is to discharge fixed amount of water every a given time. Playing with the geometry I should be able to define the interval of discharge and the amount of water to flush.