I been going through this Logic Problem today and its been killing me!

At first I got the right answer. Was well chuffed. Then I realised I made an assumption on something. Went back through what I did and realised I couldnt prove thte answer was correct!

I been killing my brain since 4pm with this now!!

Any help?

Heres the clues:

From the clues below work out the nationality of the guy who owns the fish.

► The Brit lives in the red house.

► The Swede keeps dogs as pets.

► The Dane drinks tea.

► The green house is next to & on the left of the white house.

► The resident of the green house drinks coffee.

► The person who smokes Pall Mall rears birds.

► The resident of the yellow house smokes Dunhill.

► The resident of the centre house drinks milk.

► The Norwegian lives in the first house.

► The person who smokes Blends lives next to the one who keeps cats.

► The person who keeps the horse lives next to the one who smokes Dunhill.

► The person who smokes Bluemasters drinks beer.

► The German smokes Prince.

► The Norwegian lives next to the blue house.

► The person who smokes Blends has a neighbour who drinks water