Robert Liles sez:
I used to have a large school of Rosy Red Minnows in my Goldfish/Koi
pond till 3 bullfrogs took up residence. The bullfrogs are now history
and I would like to restock with the minnows. None of the local
suppliers in my area have them though, claiming parasites. Is there a
problem with Rosy Reds?

The normal problem with Rosy Reds is that they're produced and sold in huge
bulk as feeders, and so yes, they are very often infected with parasites.
Not because they're more prone to it, but because fish handled as feeders
are less cared for and more crowded and due indeed tend to get sick more.