ALBINO CORY *URGENT*?

I have 2 albino corys in a 10 gallon with other stuff and put them in my new 30 g tank which has them a see through pinkish fish and a pregnant molly. My corys are really close and always hang out together but today I noticed one has a silverish skin on half of its body. I HAVE NO CLUE WHATS GOING ON. I condition the water the temp is at 74 f great filter fish are not agressive fed twice a day (plenty) light on from 9am till 9pm . I just dont want him to die