Hi, what is  alien planet farming?  Never heard of that one before.

When the gold aliens are set a certain way, they fill any planets in thier space with product.  If it is level 1 or less, you can take your planet in and remove all the product from these planets.   There are drawbacks to this tho.  For one, they can kill you and if you leave cannons on, they can waste your ore.  The real bad part is they can take your planet if you don't have enough defenses on it.

I failed to mention that that is just one way to take advantage of alien races in a game.  There are several ways to cash and get planets from them if you know how to do it.  I personally avoid games with those type aliens because I can outcash them by normal means, but anyone wanting to work at it 24/7 can win a game like that.   Those type games are for people that have too much time on thier hands.

If you have a planet under a port in alien space sometimes they'll buy stuff to the planet and fill it up w/ product. Then all you need to do is strip the product off and ptrade it away.

That's alien farming. It's... eh, cheesy. But some people do it.