how long to wait to add another female

[TWynnB]

I went to the LFS two days ago to purchase a solitary male pearl gourami for my tank. The store had moonlight gouramis and a quick research said they'd be a good match for my tank, so I purchased two females. I did this because the females are just as beautiful as males, and I preferred more than one for companionship.
The girls aren't getting along too well. I thought they were settling down last night (24+ hours later) since there was less chasing, but they're at it again this am. It's not severe, but obviously stressful to the one being chased. It doesn't seem to phase my Celebes or corys, but I believe it's stressing my cherry barbs as well since they mostly hide in the water sprite (unless they need longer to adapt).
My thought is to add a third, since larger groups will do better. I'd prefer not to add a fourth since will be near max capacity according to aqadvisor in my 40 g breeder but I could if it was necessary.
I'm thinking of doing so today, assuming that the sooner the better before more issues, stress, and firmer hierarchy.
I could return one, but most fish seem happier with a companions.
Do they ever improve in aggression, and if so, how long would it take? Does it seem most reasonable to get a third today? I am two days out from purchase.
Thanks for any experiences!

 

[TWynnB]

So if others are interested....
I couldn't handle watching the stressful situation and went to my LFS yesterday. He was surprised I had a mean girl, but there's always one, right?!
He suggested a male because it would become a common 'enemy' for the girls and they may be on better terms. I had read that in a group of females the least aggressive one could be bullied, so this didn't sound like a bad alternative. Either way, he said I could return fish if it wasn't working out.
Brought home a large male he had, the boy has a bent pelvic fin, the other one is broke, and a torn pectoral fin. To me this might be good (the LFS wanted to make sure I was okay with it...) because hopefully it meant he was the one being picked on vs. the aggressor. The only other male was much smaller than this one and smaller than the girls..
Put him in my tank, and he pretty much instantly hooked up with the less dominant female.
What's interesting is that this am (18 hours post introduction), the three mostly hang out together. IF the dominant female starts charging, the male steps up and diffuses it. I'd say 80% of the time the three are together now, a bit of the time the aggressor is on her own, and very rarely I see outright aggression.
I'm quite delighted that the tank is a whole lot more peaceful now and less stressful for all. Hopefully it will stay this way!

 

[carligraceee]

So if others are interested....
I couldn't handle watching the stressful situation and went to my LFS yesterday. He was surprised I had a mean girl, but there's always one, right?!
He suggested a male because it would become a common 'enemy' for the girls and they may be on better terms. I had read that in a group of females the least aggressive one could be bullied, so this didn't sound like a bad alternative. Either way, he said I could return fish if it wasn't working out.
Brought home a large male he had, the boy has a bent pelvic fin, the other one is broke, and a torn pectoral fin. To me this might be good (the LFS wanted to make sure I was okay with it...) because hopefully it meant he was the one being picked on vs. the aggressor. The only other male was much smaller than this one and smaller than the girls..
Put him in my tank, and he pretty much instantly hooked up with the less dominant female.
What's interesting is that this am (18 hours post introduction), the three mostly hang out together. IF the dominant female starts charging, the male steps up and diffuses it. I'd say 80% of the time the three are together now, a bit of the time the aggressor is on her own, and very rarely I see outright aggression.
I'm quite delighted that the tank is a whole lot more peaceful now and less stressful for all. Hopefully it will stay this way!

I am glad you figured it out.. just be ready for some babies I would assume!