What has Spook so captivated?

Its THIS (and it's blurry inhabitant, Leonard McBetta)



I have a couple of other community fish in there with Leonard and when the cats aren't sleeping or running around like nuts, they are watching the tank. I think they are convinced that I got the whole set up for their benefit!
Remus and Spook say "Any other kitties want to come watch? It is way better than the carp on TV!"