Thank you, thank you! That was everything I needed, even some answers to questions I forgot to ask!

I went and bought two baby bettas today. I assumed they were both females, as they were labelled such, but on the way home I began to wonder about my red one...

So here's a dumb question... Do females flare? 'Cause if they don't, I'm really worried about my red one... lol See, if I'd watched them longer in the store I would've realized the red one was flaring at it's reflection in the bottom of the cup, but I only watched them long enough to be sure they were healthy... The red one has the stripes and everything though! Any other way to tell with a baby betta?! They're really tiny, so fin length won't count. I just set up the aquarium, so I won't put them in for a couple days anyway.
Oh! I hate filters because mine is noisy and keeps me up at night, and it also makes the tank more difficult and time consuming to clean. So I think I'm going to try this first time with no filter, as the "girls" are so tiny I don't think they'll make much mess anyway.

Oh, and just in case, I was planning on housing two girls together, so no male/female pairs at all. So anyway, thanks again! Any help with sexing baby bettas would be much appreciated!

Thanks!