Dono - You have found a way to successfully spawn chubs. Picture is a chub. You should publish your method for growing creek spawning shiners and chubs. Shiners and chubs should not hybridize because each belongs to a separate taxonomic genus. Different genera rarely if ever will hybridize. If they did we could cross a bass with a bluegill (sunfish).

I would try trout and see what happens. You might grow some really big trout if the water stays cool enough for summer trout survival.