The only negative consequence I could see from Jim's strategy is the possibility that people that get Jim's aquarium may be then inspired to set up a real tank, and they'll try to set it up with the same fish they liked in the program -- and end up with something a bit less than "serene."
Then again, if the extent of your research into fish compatibility is only what you've seen in a screensaver, then you're pretty stupid. But I've seen people in fish stores act just about that stupid!