A Whats This On My Fish Question

Question
I know it says no pond questions, but I'm hoping you'll be able to help ID what's on my goldfish - even though it lives in a pond.  Any thoughts you can offer would be very much appreciated.  

I'd been noticing several goldfish with large pale spots on their sides, mostly the comets.  Then one of the fantails has the same spots.  His however, have spread to both sides, gills, around the tail, etc.  One of the largest spots seems to be fuzzy now.  He was lethargic for a while, but is now acting normally, although the spots seem to keep spreading.  I've been doing a lot of research on fish diseases, but can't quite tell what I think this is.  Is it fungus? Saprolegnia?  Columnaris?  Something else?  I have pictures I can send.

The pond is going on it's second year, it's about 1500 gallons, with about 35 goldfish (they bred) and a dozen rosy barbs.  We use a biofilter system and beneficial bacteria.  We have never tested water quality but will be shortly.


Answer
Hi Alison;

It sounds like it could be saprolegnia. Here is a site you can visit for more info;

http://www.fishdoc.co.uk/disease/fungus.htm

Even though the diseases are the same in pond fish, the treatments can be tricky. You might want to visit the freshwater forum at About.com. The other experts there might be able to help you more.

http://forums.about.com/ab-freshaquaria/start

At Your Service;
Chris Robbins