Not sure where you got your shiners from but I hope you trust your source or your sorted those before you tossed them in.
I would make a not to sort my FHM as they tend to have surprise fish in them more than shiners.
Just want to let you know as in many cases it has been shared that people have ended up with the wonderful Bullhead in their pond and not have any idea where it could have came from.
Just wanted to let you know and I am sure you will get more feedback from the experts on this mater.
Thanks