Tropical fish kept for home aquaria include the following:
- Wild-caught specimens.
- Single-species individuals born in captivity. The latter category includes lines selectively bred for special physical features, such as long fins, or particular colorations, such as albino.
- Hybrids of more than one species.
Recreational SCUBA divers are often enthusiasts of tropical fish as well. Some keep lists of fish species they have observed while diving, especially in tropical marine environments.