Love your biotop, I saw you want to put a Betta in there. There's not much of a difference between males and females, the only thing I can think of is looks (fin length) & the fact that in a large enough tank you can keep more than 1 female. I have a female Betta alone (I was told she was male) in my planted 13 gal & she's happy & active.
Thanks so so much for taking the time to send me this! I'm glad to hear solo females can thrive, because looking at the tank that's where my thinking is. It's a messy, wild-looking tank and a fancy, brightly coloured boy with huge fins might look out of place. So it's probably going to be a neutral-coloured, "wild-looking" girl (I've seen some nice blue-brown-green ones at my lps). Thanks again for the advice :D
