I've possibly come across another fish. I know this is an older topic, but the question is still being asked a lot.
The Japanese ricefish (Oryzias Latipes). They come in different bred colors and grow to a max. size of 3 cm. They leave their own fish eggs alone, not sure how that translates to salamander eggs though. They can be kept with freshwater shrimp aswell like Cherry shrimp (Neocaridina davidi).