Ulcer or infection?

Question
My goldfish (comet) has a ulcerated lesion, about 1.5cm x 1.0cm, on its side with loss of scales and skin. There is also a small white lesion, about 0.3cm diameter, on the side of the head. Apart from that it is very active and feeding well. We are not sure how it came about, but it has been present for the past few weeks. We are not sure what it is but think it may be due to trauma rather than an infection seeing it is behaving so normally otherwise. I have taken a photo.

Answer
Hi Gladys;

Keep his water very clean and get a product called "MelaFix". It is a natural fish remedy made by API. Here is a good web page about it's effects on ulcers;

http://tinyurl.com/2sfmh9

I hope he feels better soon...

At Your Service;
Chris Robbins