The Colony Manager is available for each settled colony. If the selected planned is unsettled only the Planet Info is visible. It gives information on the following values:
- Income [in Credits]
- Economic Rating
- Life Support Costs [in Credits]
- Industrial Output [in Output Units]
- Morale (for each race (or faction?) living on the planet)
- Imperial Population
- Civilian Population
There is a slider that lets you distribute the Industrial Output between Construction and Trade. While set toward Construction, any unused production generates normal money via on planet trade. When set toward Trade, trade goods are produced for shipment off planet (though this doesn't generate any direct income unless the trade good is shipped via freighter somewhere). Redirecting towards interplanetary trade will also take a few turns to "ramp up" trade good production. 
Also Overharvest is possible with a slider in the Colony Manager. If necessary it is also possible to abandon the colony with the "Abandon Colony" button.
The last two sliders in the Colony Manager allow you to set what the maximum civilian population on the planet should be and what amount of the planetary production dedicated to construction should go to ship construction. What is not going to ship construction is used to develop the planetary infrastructure. Moving the Civilian Population slider all the way to the right will maximize civilian population, but when the colony achieves high population it will begin to cause biosphere damage. Populations which have hit their maximum will also incur a Morale penalty.