Buying fish from US

[Frogger]

According to Customs Canada Website:

When importing an aquatic animal, an import permit will not be required when the owner can:

present proof of their identity and their ownership of the aquatic animal to the inspector at the point of entry into Canada
attest to the fact that the pet animal has not been taken to a show or display outside of Canada
keep the pet animal in their household aquarium
ensure the pet animal is not exposed to any aquatic animals other than those kept in the household, for one year following the importation
not import another pet aquatic animal as listed below for the period of 90 days after the importation
keep all records of the importation
- and -

The pet aquatic animal is one of the following susceptible species of finfish:

Barbonymus gonionotus
Carassius auratus
Colisa lalia
Danio rerio
Glossogobius giuris
Osphronemus goramy
Oxyeleotris marmorata
Poecilia reticulata
Puntius sophore
Symphysodon discus
Toxotes chatareus
Trichogaster pectoralis
Trichogaster trichopterus

Not sure you need anymore than that.