ebb and flow timer and timing questions

[tfrost2002]

I am planning to grow tomatoes with a new system I am building and would like to know if anyone would give me a little help on a couple of issues. I would like to know how often an ebb and flow system should cycle, for what length of time each time and what timer to purchased to make it work? I hope this makes sense. I am very new to this.

Thank you for your help.