Starting sorority tank questions

I will be starting a sorority tank this week(probably Friday) and I have a few questions:
1. I want to make sure this tank is alright: 10 gallon, w/ filter, air bubbler, and will possibly be getting heater if I need one, there is already one female betta there and she seems healthy without one though. This tank has a female betta in it along with a platy that I will be moving to a separate tank, so it is well cycled and clean.
2. Is 5-6 females a good number for this size tank?
3. If I remove the one female from the tank I have now, redecorate, then add all the bettas at once, will this reduce the chance of the betta I have now immediately trying to be dominant because she was there first?
Please tell me what you know!
P.S. I will try to post pictures once I get all my girls. I'm very excited!

Hi & welcome

I dont wish to be the bearer of bad tidings, but in my opinion 10 gallons is pushing the limits for a sorority If you can really bulk it out with plants and decor you may get away with 4 females. Although more is better, 10 gallons just wouldn't be able to support any more.
Re-scaping and adding all together is always a good idea

like van said 4 should be fine. you might be able to get 6 corys aswell aslong and you have a good filter with atleast 10x turnover.
i would get a heater becuase the temp need to be quite stable and at about 27C.

my sister has used a 10 for her girls, but there was constant CONSTANT bickering. then my dn's baby angel fish died (go grandma for buying her the most delicate fish possible) and she switched the bettas over to the 20 high. no more constant bickering.

I'm not great with knowledge on sororities, but lots of plants and caves helps as the plants can break the line of sight between the fish.

Also think a heater would be a good idea - I know they're often not sold from heated containers, but they do need warm water

I think what I will do is have five and get a lot of plants and hiding places. I will get a mini-heater too. Thanks for info!

Yeah with a 10 gallon you definitely want a heater, 28c is what most people keep the heat at, I have mine at 30c and they are very active and happy. You'll also want to get tests if you don't already have them and maybe check out the pink link for Betta paradise, they have info on all sorts of neat things at the shop. Great shop by the way Netty!

Thanks everyone for the advice!