fish schooling sizes

Hi, I've been wanting a more planted and full tank for a while now. I have a 200l tank with around 27 cardinal tetras, 3 red phantoms, 6 kuhli loaches and 1 panda garra. Once I've put more plants in and set it up exactly how I'd like it, I'd love to get some more fish as it's looking very...

I have 3 Sterbai Cories at 2". If I buy 3 more Sterbais at 1" will they all 6 school or no?