Fish
The smallest fish is the Philippine goby that is less than 1/3 of an inch when fully grown.
The largest fish is the great whale shark which can reach fifty feet in lengh.
Fresh water fish live in water, rivers, lakes, or even aquariums as pets or as a hobby. Forty percent of all fish species despite the fact that less than .01 percent of the water on the earth is fresh water.
Salt water fish are found all over the world in salt water. Saltwater is found in oceans and seas
Warm water fish are found in warm water.
Many coldwater fish are large enough that they are only suitable for ponds. Cold water fish do not require a heated tank.