They're both relatively slender bodied with very long flowing tails, pearly white in colour except for a single elongated oval head/dorsal marking which is bright red. They look like what we call Sarasas over here which are red and white, but these two have reversed colours being predominantly white and red, and look just like a Tancho koi, colour wise. I seem to recall when they were smaller their body colour seemed to be a more pinky white, but they're both definitely a clearer white now.
The pic above shows one of them it's not an ideal shot as I've zoomed in on an old pic and cropped it down a lot, any more zooming and it goes too out of focus! Any clues?