red stains on fish

Question
Our silver/gold fish has grown a red stain under its skin. It looks like blood. We have changed the tank water and it has faded a little back to sliver.

Answer
Hi Mary-Anne;

How big is the fish?
What size tank is he in?
How long has the tank been set up?
How often do you usually clean the tank?
Does it have a filter?
Are there other fish in the tank?

Let me know as soon as you can....

Chris Robbins