Be careful that your bullfrogs don't eat your fish! Turtles will also try to take a bite out of fish, too. Native fish can carry diseases that koi are not resistant to. It's best to stick with the carp family in ponds. Never release pond fish into natural waterways. Enjoy, Gail
There are minnows in my pond, all three of them have gabusia[spelled wrong] as well as fat head minnows. Rosie reds have there own pond but they do well with koi and goldies. They are all none agressive and fun to watch.