Hey there,

When you say the frog swims in circles does she have the ability to move both her hind legs? I mean, she is not swimming in circles because she can only move using her right-sided legs, right? Is your frog able to surface for air properly? It not she should be moved to a large tupperware container or a small tank with shallow water with daily water changes so she does not drown.

I'm not entirely sure what would cause swimming in circles besides a stroke, though I suppose a bacterial or fungal infection could cause this too. A stroke can happen if a frog is kept at high temperatures for a prolonged period of time, though 75F would be considered an 'upper' safe temperature (68F to 72F is ideal). Another cause for stroke would be being fed fatty foods like beefheart, besides gobbling down some guppies, what was your frogs main diet?

Last and obviously biggest concern, the fish. Fish carry all kinds of diseases and parasites that could afford your frog. It's highly recommended that african clawed frogs be kept in a species only tank.

Were these danios newly purchased from a pet store? A lot of stores (especially PetSmart and PetCo) use shared filtration between all their tanks, so if one fish is sick, chances are good it can affect another tank.

If the new fish were purchased recently were they quarantined at all? If the fish had some kind of disease or parasite it could have affected your frog when he ate it.

Assuming not a stroke, if it were a bacterial infection it could be treated with Maracyn 2. At this point though I am not entirely sure.