One of my mollys the siver male always seems to look skinny the others have always been fine and have little bellys. He eats well ive treated the whole tank not long ago as he seemed to have ich and was scratching on things.He had lost his silver colouring back then and had the shimmys. He seems to be doing much better after the treatment and has his colour back better than ever so he seems healthy and also so much happier since turning the tank brackish. Could this just be the way he is? Or should i be concerned?