Freshwater
freshwater and saltwater
Depending on the type of eel, yes.
Unagi (うなぎ) is freshwater eel. Anago (穴子, or アナゴ) is saltwater eel.
no usally in freshwater lakes or ponds that have running water or stocked in the pond or lake
The fish that looks like a snake is called an eel. Eels have a long, snake-like body with no scales and can be found in both saltwater and freshwater environments.
no
they are both saltwater and freshwater
They contain saltwater and freshwater
The Persian Gulf is saltwater, not freshwater.
A freshwater eel is a type of eel. An eel is a long thin fish. The freshwater eel lives in rivers and lakes for most of its life and spawns (or has its young) in the sea
Saltwater is heavier because saltwater contains salt which adds to its overall weight. Freshwater does not have any dissolved salt so it is lighter then saltwater
Freshwater eels come in a few varieties such as the peacock eel, tiretrack eel, fire eel, etc. There is also what is called a freshwater moray, though I believe this eel to be mainly brackish and not truly fresh. Freshwater eels also include a species called the Polypterus, which include the Bicher which is commonly called the Dinosaur Eel. Freshwater eels are usually smaller and less aggressive than their saltwater brethren and generally spend alot of time buried into the substrate. There are eels from different locals offering choices to better suit the other tank occupants.