Generally, fish with good meanings are used, such as arowana, which symbolizes dragons. Other feng shui fish generally use goldfish. Koi fish, a symbol of good luck, is mostly developed and has many tropical fish, so it is not limited.
Feng shui fish are mainly used to transport wealth and turn into feng shui. They are very formal and exquisite, but there are not so many requirements for domestic use. So, don't be too limited to tradition.