No picture? "New Scientist" is a bit too delicate. Feeding the fish is the most gratifying part of having an aquarium - it's the only time you interact with your pets. No, the downside is definitely scooping out the dead fish and flushing them down the toilet. Presumably robots who are floating belly-up must also be removed, but perhaps it doesn't catch at your heart quite as much...
Robot pike pictures and video
Dongle the mechatronic fish
Tiny robot fish with artificial muscle and very dull video suitable as screen saver.