To avoid fin nipping/aggression with zebra danios, it's recommended to have at least 5-6. I honestly don't know if that can be done in a 6,6g. I'd be worried about water quality/bioload issues.
Chili rasboras are a good idea, very colorful! I think Msjinkzd had done for sale in the marketplace!
Habrosus corydoras (dwarf type, max out at 1") would be a fun addition to your tank, you could easily have 8 with chili rasboras or a calm betta. Habrosus have the cutesy wiggly butts!
. There's also pygmaeus & hastatus corydoras.
Chili rasboras are a good idea, very colorful! I think Msjinkzd had done for sale in the marketplace!
Habrosus corydoras (dwarf type, max out at 1") would be a fun addition to your tank, you could easily have 8 with chili rasboras or a calm betta. Habrosus have the cutesy wiggly butts!