because saltwater fish must be live in saltwater
saltwater
They are Saltwater fish.
Saltwater fish are hypoosmotic.
the rarest fish is the super sized golden trout/salmon cross breed
Saltwater fish live in the saltwater seas and oceans around the world.
There is no real data to tell us what the rarest marine fish is. Likely the rarest fish has not yet been discovered, because it is so rare.
A saltwater fish tank can be half freshwater and all of the saltwater fish will live but not for very long.
Because saltwater fish can only breathe in saltwater (as in the ocean) and freshwater fish can only breathe in freshwater (as in tap water.)
Well, there are 2 types of fish, saltwater fish, and freshwater fish. Only put in saltwater if you own a saltwater fish. Note: Saltwater fish could live safely in freshwater, but freshwater fish will suffocate in saltwater.
saltwater
saltwater fish need to breath in saltwater and not fresh water. just like we need to breath in oxygen and not carbon dioxide.