I have seen many versions of this puzzle. I am posting the version from Peter Rohde's blog where you will also find the answer.
There are 5 houses of 5 different colors. Each house is occupied by a man of different nationality. The 5 owners each drink a different type of beverage, smoke a different brand of cigar, and keep a different pet.
The clues are as follows:
* The Brit lives in the red house.
* The Swede keeps dogs as pets.
* The Dane drinks tea.
* The green house is on the left of the white house.
* The green house’s owner drinks coffee.
* The person who smokes Pall Mall rears birds.
* The owner of the yellow house smokes Dunhill.
* The man living in the center house drinks milk.
* The Norwegian lives in the first house.
* The man who smokes Blends lives next to the one who keeps cats.
* The man who keeps the horse lives next to the man who smokes Dunhill.
* The owner who smokes Bluemasters drinks beer.
* The German smokes Prince.
* The Norwegian lives next to the blue house.
* The man who smokes Blends has a neighbor who drinks water.
Question: Who owns the fish?