Red and black fish (maybe trout and carp) in the Golden Temple sarovar in Amritsar

The holy tank in the Golden Temple complex contains a number of fish, and when you move close to the edge of the tank, you can see these fish frolicking, trying to get air and seeming to breathe air (although they get the air from their gills). Some of these fish are several inches long, but nobody was able to tell me the species of these fishes.