*and probably not any of your other fish either- adf do best species only.
So, let’s talk about Hymenochirus boettgeri or the african dwarf frog. This species is recommended as an ideal tank mate for domestic bettas by many, many sites. Unfortunately, these adorable little frogs are not as perfectly suited for bettas as they seem!
You might think, these species will get along great! Frogs look nothing like bettas, so a betta shouldn’t be threatened by its presence, right? However, appearances aren’t the only important thing about tankmates, and once you look closer, the arguments for housing them together fall apart.
The first thing is temperature and pH. Domestic bettas are acidic water, tropical fish. pH for them should be a bit under 7, and temperature should be 78-82 fahrenheit. In contrast, the african dwarf frog likes it cooler and harder. 73-75 is the recommended range for these guys, with a pH of 7.6-7.8, much more basic than domestic bettas do best in.
Next, temperament and physiology. African dwarf frogs are poor swimmers with poor eyesight. They can be easily outcompeted for food by the more boisterous betta. The betta very well might still attack your dwarf frog(s), easily killing or maiming them. Surprisingly, these small frogs will try to eat anything they can fit in their mouths, and are capable of hurting a betta if they try. There is more than one report of african dwarf frogs killing or fatally injuring bettas!
In the end, due to temperature and pH incompatibility, as well as issues with temperament, it is best not to keep your african dwarf frog(s) and your domestic betta together. Instead, give them species only tanks that cater to their unique needs. Both species are excellent pets and fun to watch and take care of, and they will be just as entertaining and enjoyable on their own.