good luck with this dave, hope it goe's ok for you.....This next part is for the eye's of people like wilder to read and see what they think
<your not worthy dude so look away now> hehe this part was what i forwarded to you yesterday
"aurantimaculata eroding disease:
This is something thats been seen in a couple of our members aurantis, i had to euthanise a male i had due to it. Even though this has been refared to as aurantimaculata erosion, this doesnt mean it cant happen to other species, however i havent heard of it happening to any as of yet. The cause of it so far is unknown, however its thought to be bacterial as it has simalar symptoms to Columnaris infections. It starts with the fins turning grey in small areas and then suddenly it starts eroding the fins quickly followed by the scales at the base of the skin lifting and starting to erode, through out this theres patches of exess mucous over the body varying in size. I managed to get it under control with methelene blue but this only lasted two weeks and then it came back worse than ever. There is a member on here with some quite graphic photos of just what this thing can do in a short space of time (cant remember whos has them though). This is a guide of how to gain controll of it when you first notice signs of it.
The first stage is isolate the fish with the signs, then begin treatment imediately. There are various things that can be attempted with this these are;
Acriflavine to either 5ml per each liter of water for 2 to 4 days, or 10ml per liter for 10 days (however this is a risky treatment!!). If you can get hold of it you can use Chloramphenicol mixed with Acriflavine at 4ml per liter Acriflavine and 40mg Chloramphenicol per liter for 12 hours(note with all treatments it is advised to add extra aeration as treatments can strip oxygen out of the water).
Methylene blue at 3ml per liter for 5 days, perform a 25% water change and leave two days(preferably adding carbon to a filter) and then repeating the dose for another 5 days.
If the erosion gets to the base of the fins it would be advised to get a wound sealant and use this to stop and secondary infections occuring and also stoping any more erosion, any of these items can be found at koi specialists, kusuri even do a kit with everything you need to dress and protect a wound on large fish, this would come in very handy to sort this kind of problem!
well i hope that no ever has to use this information, but if you do this will hopefully save your fish, remember even when you think its under control, closely monitor your fish for a couple of weeks after treatment has stoped as it can come back in an instant.