You can tell if a gourami is male or female by assessing the following physical features and behaviors:
- Body shape – Male gouramis tend to be slimmer, while female gouramis have larger, rounded bellies.
- Size – Female gouramis usually grow to be longer and bigger than their male counterparts.
- Coloration – Male gouramis have brighter, more vibrant colors than females.
- Dorsal fin shape – Female gouramis have short and rounded dorsal fins, while males have long and pointed dorsal fins.
- Behavior – Male gouramis tend to be more aggressive, especially towards each other, while female gouramis are more docile and gentle.
Note that color and size differences may be harder to spot in certain varieties, but the methods for comparing their fin shape and behavior still apply.