I wil be making mine soon, but here's a hint: You do not need a complicated 'controller brain' bucket with relays/float switches etc...
You could simply set up your timers to run for say "8 minutes fill," which depending no your pump, would fill it exactly to the level you need. Also, you could add a simple 'overflow' on a bucket in case something goes wrong to replace the float switches to prevent a mess.
I am thinking with timers and pumps you could set up everything without even needing a 'brain.'