Boesemani Rainbowfish M to F ratio?

[Vladka]

I have a 65 gal aquarium, everything is going well
2 angelfish
2 BS plecos
1 red tailed black shark
2 albino dojo loaches (looking to expand but hard to find healthy ones)
7 male boesemani rainbowfish

So I would like to have 12 rainbows in the tank, and I was under the impression that I could house just males, and they're much more colorful so that's what I did.

In my search lately it has been increasingly difficult to find more males and it got me thinking... do I need females?
Many of my males are starting to look best up, or missing some scales. At first I blamed the shark; but after some rearranging she seems to be pretty chill and only occasionally chasing rainbows if they come into her territory.
But I've been watching and the males challenge each other pretty often or even nip at each other. Could this be due to frustration?

Do you guys think I should add some females or just get 5 more males (if I can find them)
If I should add females does it matter how many? I know just one would likely get abused but how many do I need?

Also do females just stay gray forever? I used to have a couple an I gave them away because they were pretty ugly compared to the males.

 

[V227]

I think the alleged experts report the ratio should be 1 male for every 3 females. I've
kept Boesemani rainbows and did virtually the same thing you did. If I remember correctly I had 5 males and 3 females. I believe the presence of the females made the stronger males color up more. My females weren't gray, they were the same color as the males, just muted.
Granted, the female Boesemans were quite busy but suffered no health issues. My suggestion would be to stock only females to the remaining empty slots of your school. It will likely add more color and movement to your tank.

 

[Vladka]

Does anyone else agree with the 3:1 ratio? All the females I've seen have been REALLY boring and dull. I know live bearers need a 3:1 ratio but I was hoping rainbows could pass on that.