Congo frogs

[SpeedofaSloth]

Hello
We have a 54l tank, started in January, housing 2 guppies and a zebra snail.
Our (fish-in) cycle looks relatively stable now so DD and I popped to our local fish shop for a better water test than our strip tests, and a look for tank mates. Ammonia 0, nitrates 0.
She's fallen in love with two tiny congo frogs.
From my sketchy internet research I think our tank might be suitable, but I'd love to hear from more knowledgeable people about whether we'd be housing them well, or not.
We have an internal filter and artificial plants and a pottery cave, plus 4 live moss balls. TIA.

[SpeedofaSloth]

Hmm. Some further reading and asking around reveals that frogs are tricky to keep happy. Perhaps this is one for when we're not beginners....