My fish look like their skin is coming off

Question
In the past month I have had 4 fish die suddenly. Their skin looks like it fell off and then they die. What could be the cause of this. I only have two fish left and one is my older parrot fish that I want to help.

Answer
Hi Stephanie
Did it look like white patches or stringy material on the fish?  Or like white flaking?

Do the 2 fish that are left have any symptoms?  
And, did the other fish show any other symptoms at all, like maybe their fins/tails were frayed or splitting, any discoloration on their scales/skin,etc.?

Did you add anything new to the tank before they got sick?

Christy