h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Nobody seems to believe me. Are they all part of a big conspiracy or are they afraid to look at the truth?
I've got to get proof. Today I made a plan.
The first step is to hide between possible conspirators.
I bought a black suit and a black tie.
The next step is to build a trap. The aliens have advanced technology and are capable of entering and leaving my house without a trace. I don't think I will actually be able to catch one. I will try to prove they do exist and do ate my fish.
I bought a webcam and a microphone and are busy with hiding it inside my house. When all equipment is installed and tested I will bring in some bate and lure the aliens to come inside the view of my camera.
The bate will have to be something they can't resist. After thinking really hard I came to the conclusion that the best thing would be a cow. However my room isn't very big and I see a lot of trouble ahead bringing a cow to the first floor. I settled for the next best thing:
fish. This will also proof my secondary mission, to proof that aliens ate my fish. I will get me a fish but have not yet figured out if I should do this in secrecy or doing it right out in the open. I fear attracting to much attention will warn the aliens something is goint on, on the other hand if they don't know there is fish they might not come at all. This is a very difficult decision I will have to take!