Perhaps comets are different than koi. I have several comets which had
small bacterial sores. Once remedied all the scales have now grown back.
You can slightly tell where the 'injury' once was because they are not quite
the same height, but barely noticeable.
Bill

"Gary" wrote in message
...
I was given a large ( almost 24 inches) Koi. It had lost numerous scales on
either side. I believe the cause was trauma rather than a disease process
(there are 2 long lesions of 3 rows wide of scale loss) . I have had the
fish for over a month and it is doing just fine. My question is. Will these
missing scales grow back? Is there anything that I could do to help the
problem? Thanks