Rehash?
District 9.
Alien Nation.
I haven't seen it. But I read the synopsis, and immediately thought I saw it already.
Aside from the excuse for how the aliens got here and were stranded it's not really like either of those and the plot is completely different.
You might as well be saying that Star Trek and Star Wars are the same thing because they both have Star in the title and there's space ships.
Most sci fi shows (heck, most shows of any kind) share at least some traits with other shows. It doesn't make them the same thing.