Was playing a game and I noticed that a planet I owned was not increasing in size after I added a farm to it. I sent Stardock a couple of SAV files showing this behavior. I got back their reply and I am passing on.

"The reason that the population of Nidil I (and I noticed, a couple other of your planets) is not growing is that there is an additional cap on the population of a given colony outside of food production that is based on the planet quality. Basically, once the population of the colony reaches 20 * (PlanetQuality + 1)^3, the population stops growing, presumably because the planet just isn't hospitable enough to support that many people. This is what happened on Nidil I; it has a pretty low planet quality, so it can't support more than the 7-odd billion people it has on it already. Thanks for the report, though, and I hope that explains what's going on well."

I noticed that you can transport people to the planet and the farm will support them, but the planet is not going to grow on its own.

I am not aware of any thread where are posted the subtle mechanics of this game. If there is none, and you know of something worth passing on, you can post it here.