I got 2 yo-yo loaches yesterday and was thinking of getting another few, to keep them all happy, but now am actually thinking about getting a couple adolescent Clowns... Will they all shoal together and keep each other good company?
Some will and some won't. Yoyos, Clowns, Striata, Queen Loaches, and Sinibotia Robusta are all fairly peaceful and can coexist, whereas the Modestas are bastards and will chase smaller botias. Check out my loach blog for loach compatibility recommendations.