Changing colors

Earlier I mentioned that I lost my favorite fish from last winter, a fish which had a black tail and fins. I was wondering whether the other fish had done him in in a jealous rage. My friend suggested that perhaps the dark color had faded with the summer and I summarily dismissed the idea. Well, now I think she may be right. I looked in the upper pool today and the orange fish with the black markings is now an orange fish with white markings! The down side to this discovery is that I this could be the sign of some disease in the fish. I tried to catch the fish in the upper pool in order to make sure that it is ok, but I couldn't with the net that I have - I need a new net, also better technique. All I managed to do was to freak the fish out. But it did move very fast and inventively, and it looks fine as far as I can see, so it probably isn't sick.