Have you ever talked to fish? If you can incorporate the feelings of your fish into breeding systems, life with your fish can become more comfortable, fun, and a greater experience overall. In breeding pets, owners often cannot properly understand their pet's internal state, which can lead to impaired health-or worse, loss of life-for the pet. In case of fish, such situations are more likely to occur than with dogs or cats, since owner-pet communication is more difficult with fish. Although fish are the most bred pets , information and communications technology (ICT)-based solutions for accelerating owner-pet interaction have not yet been sufficiently explored. We present "TalkingNemo," an aquarium fish breeding system that enables interaction between owners and their fish. TalkingNemo detects the condition of fish and their aquarium via a camera and sensors attached to the aquarium, and notifies users with speech balloons as from the perspective of the fish (Figure 1). TalkingNemo empowers us to breed fish in good condition over a longer period. This paper introduces the architecture and evaluates the results of TalkingNemo.