Stocking Betta Tank Help

[GARZX9R]

Hi All, I'm new to the Tropical fish scene and about to start stocking our first tank, tank is 40lt, gravel bottom, heater set to 78/80 degrees, live plants, rocks and bog wood, fluval filter with carbon medium, went window shopping for which fish we like and what is compatible etc, we saw a number of betta in different shops and wow we have fell in love with them, after a little research on the net tonite i gather you can only keep a single male on it's own, so if i get one what other fish could it live with hassle free,
Species
males/females
numbers
your help would be greatly appreciated

thanks stu
oh, my readings are ammonia 0, nitrites 0, nitrates marginally above zero. ph about 7

 

[horseten]

Anything that wont eat Mr.Betta(duh), has the same tank requirements (roughly),has short fins,no vibrant colors, and is not another labrinth fish. You could also do a tank with multiple feamale bettas.