I hae always had fish with my frogs. As long as your frog can't fit the fish in its mouth they are fine. My frogs generally don't bother any of the fish. I have a variety: parrot cichlids, goldfish, a betta, cory cats, pleco.
I would suggest trying the frog and the fish together and see how everything goes.
If the frog continuosly tries to eat the fish and the fish is stressed then i would separate them.
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~Crissy
3 Female African Clawed Frogs: Nemo, Casper, Pebbles
2 Male African Clawed Frogs: Amtrak, One-Eyed Jack
3 African Toads: Fiona, Shrek, Pickles
1 Pac Man Frog: Freddie
1 Ragdoll cat: Carman