hospital tank

I bought a new plastic storage box for my QT/hospital tank. It holds five gallons, and has stiffer material, the sides don't bow out when filled with water. I'm not sure what to think of my fishes' condition this morning. Two look the same- the worst one, no more flaky appearance on the head. The area now looks grey with black marks. Is it dying tissue? not sure.

She also looks too fat- constipated? and gills more rosy than normal. Currently not feeding them.

It's hard to get a picture- the fish are shy of the camera, move quickly and the sides of bin are somewhat translucent.