My upside down catfish Gina looks exactly like your typical upsidedowner. However she recently moved into a large mug that is in the bottom of our tank. She spent about 2 days in there, coming out only for feeding. I was vacc'ing the gravel today and bumped the mug, she came out and was a light sandy brown color. Really really light in color. Of course I freak out and jump online and start frantically google searching but found no input on this. What is even stranger to me is that not even an hour later, she was back to her normal colors! Completely! She hasn't gone back in the mug and is lounging on her rock. Is this normal? Could the lack of light caused her color change? I'm very curious!