Laser pointer

i have a random question.  Yesterday one of my roommates was playing with a laser pointer and he pointed it at the tv and it reflected on the back wall.  I told him to point it at the tank to see if it would do the same and it did.  My clown and sixline started chasing the light around the tank trying to get it.   Is this a bad thing for the fish at all?  They just swim around in circles arount the light trying to get it.  My goby sometimes tries to eat it and some times goes back under the rocks, and my cromis just swims away and hides.  After seeing the goby and the cromis' response i just shine it close to the clown and the sixline.  Also i try not to shine it right in their faces just along the sand or on the rocks.  Just want to make sure i am not annoying them.