Can you please check if I am caring for her correctly?

[Bombina Bob]

It sounds like you are taking care of her decently. You would be ok putting another frog in around her
size, but I would keep to 20 gallons per clawed frog. What kind of filter do you have for her?

[Gemma]

You should definitely use the filter, which you should make sure you leave running at ALL times (apart from during tank maintenance). I would highly recommend doing some research on aquarium cycling. In short, your frog's waste products break down into ammonia, which is toxic to her. If you leave your filter running, colonies of helpful bacteria will grow in it, which will convert ammonia into nitrite. This is also toxic to her, but other sets of bacteria in your filter then convert nitrite into nitrate, which is less harmful to your frog, and excess levels can be removed during your weekly water changes. Using the filter (along with your water changes) will keep her water chemistry safe and stable, which is important for her health, and it will make your tank maintenance much easier.