Raising the Population Limit
Occasionally, you will come across a world with a very low population limit. If you need to raise the population limit at a world, you can use your industry to do this, at the cost of 5 metal for each one unit increase to your population limit.
Robots, of course, are not concerned about population limits.
If your world's population is less than 5 to start with, then it cannot support the minimum population necessary to work the industry to raise the population limit. In this case, you will have to migrate more population to this world from a neighboring world. If you migrate more people than the population limit will support, they will die at the end of the turn; but before they die, they can work the industry for one round. This is an expensive way to raise the population limit, but unless you are a Positronix, it is the only way.