Queen Loaches schooling with other species?

My 55 came with 2 queen loaches (mom's old tank). They're older, probably 6?7? years old. I was originally planning to get 5-6 more queens to school with them, but while checking my local store every week looking for more queens... I got carried away with the plecos. (albino bristle nose, 2 reg bristle nose, 1 clown) I don't think there is room for that big of a school of queens any more. (although I do have lots of caves and plan to add more). Also, I'm not convinced I'll find more queens any time soon, they have them very rarely. Has anyone had queens school with a more common, smaller loach? (zebra? kuhli?) I'd like them to be able to school. They seem so lonely and shy with just 2 of them.