Madascar Rainbows - How Many In A School, What Sexes?

[upNdown]

I picked up a few madagascar rainbow fish on a whim, for my community tank.  Everybody's getting along well and they're cool fish.  So if I want to increase the school to make them happy, how many should I have? 5? 6? more?  Also, do the sexes matter?  I know with livebearers, it's often suggested to go 2:1 male to female - does the same hold true for these guys?

 

[KittyKat]

Schools are best at 10+ fish. Rainbows can normally be kept at a ratio of 1m 1f and some people keep 2m 1f (I would prefer the former for myself).

 

[upNdown]

Thanks for the quick response.
I don't think I'd be comfortable adding 7 more to the tank - I feel like adding 2 or 3 more would be pushing the limits of the tank capacity.  In your opinion, would a school of 5 or 6 be better than 3? Or do you think that anything less than 10 is equally non-optimal?
 
This is a 4 foot, 50 gallon tank (1.2 meters, 190 liters.)
Current population:
 
1 Pearl Gourami
1 Dwarf Gourami
1 very small pleco (not sure what kind, but not common - he won't get big from what I'm told)
3 Swordtails
3 Madasgar rainbows
7 goldskirt tetras
10 neon tetras

 

[hobby5]

So why did you get the rainbow fish in the first place? It would have been much wiser to up the numbers of neons and goldskirts.

 

[upNdown]

Because the rainbow fish looked cool.  As it turns out, they are.

 

[milosilo]

If you are limited in numbers you can have, I would keep just one sex. When I had a smaller tank I kept a group boesemani ranbow - 3 males and 1 female. They used to annoy the female so I swapped her for another male. The group of males got along fine and had no one to harass.