Clown Fish
No, clown fish are marine fish and tetra and guppies are freshwater fish.
i think you would need a medium tank for your fish.
No Clown fish are good with guppies although it is possible to keep clown loaches (Botia macrocantha) and Guppies together for a while. Don't forget though that Botias are shoaling fish so they should be kept in groups. They also grow to around 14inches long so need a large tank.
Trigger fish could easily eat a clown fish without the protection of an anemone. Even with some protection an owner would need to insure the trigger is fed regularly to prevent injury to tank mates. Sea horses, while probably not particularly edible, are difficult to keep and may not be compatilble with agressive tank mates.
they hide in the anemone
That depends on what you mean to say. For example, if you have one angel fish in the tank you could say "That's the fish's tank" meaning that is the tank for the angel fish. If you also had a couple of clown fish, you could refer to the tank as belonging to all three fish by saying "That's the fishes' tank." Slightly different spelling and punctuation
What is the unusual characteristics of the clown fish?
Yes it is, but you may have trouble adding another one later if you just put in one at the beginning. It depends on the type of clown fish you add. If you plan to have multiple clown fish, consider adding them all together.
Simple You mix some rock salt in tank
yes fish are easy to care for since all you have to do is feed them clean a tank and care for it i have a betta fish which is SO EASY to care for
Clown fish in french is poisson clown