I recently added a few new fish to my aquarium about 3 days ago. All them have been doing good. However, when I woke up this morning one of the blue Micky mouse platys was sitting on the bottom in a corner. I assumed that one was a female due to the blue not being as vibrant as that other but this morning she was totally pale with dark almost black splotches on her body. She would swim erratic then his. She was floating around so I put her in a net. That way I won't lose her and other fish won't get her. I'm not sure what happened to her. I didn't see ich on any of the fish and the rest are doing fine. The other platys are still a bit shy but I'm assuming that's normal. If anyone has some insight on what happened, I would greatly appreciate it. This is my first time keeping platys. Water parameters: pH: 7.4-7.6 Ammonia: 0 Nitrite: 0 Nitrate: 0 Temp.: 75° My tank is well established.