Question about divided tank

[cgchad]

OK I have created a monster apparently. Instead of stopping with the 2 males and 1 female that we have, my fiancee wants to have a sorority, along with the 2 males. (She needs a Betta intervention to stop her).

So now up pops this 20 Gallon Long tank, and mysteriously a heater, filter, and 2 dividers. The way I have this set up at this point is, there is 2 smaller area's at either end of the tank to house the males (In about 8 inches from each end.) The remaining area (About 14 inches of space) is where we kind of plan to put the sorority. The filter is located in the center area, as past experience has taught me that this is usually the best place on longer tanks. The heater is horizontally installed, in the same general area, to help circulate the warmer water.

I recommended to her that the sorority should be no less than 4. I read that somewhere. So is it the consensus that this would be an OK set up? Or should I re-structure the tank?

Since its cycling with nothing in it right now, I figure this is the best time to make changes. I figure I would like to make any necessary changes before I plant it.

I haven't tried sororities before, but have had read all the postings about setting it up here, so I think I have a good plan on what the next step should be. That and my past experience with community tanks.