Hi all - Well, my first question of the new season. You trained me well last
year, so I already checked water parameters, nonetheless here's the problem.
Some comets seem to be missing some scales. In some cases it's just one or
two here, a couple more there, maybe 10 total at random. In others there is
more missing and will sometimes look like a wide scratch or abrasion. Most
recently I just noticed one who has what appears to be a large scrape right
on his forehead (all the others are on their sides). I have shubunkins,
short fin and long fin comets, a few fantail goldfish and a few small koi.
Only the comets seem to have the 'problem', and most of them are the larger
(5-6") commons. Only about 10-15% are affected at all. No signs of fin rot.
I have seen a couple of great blue herons flying by, but I dont believe any
fish are missing and it seems unlikely the same fish would have been wounded
a number of times and most of the others unharmed. They are not skiddish.

The only three wild guesses I have are
1) one of our 4 cats does get down and nearly put his nose in the water
occasionally, watching the fish. However I have never observed it actually
swiping at them. I was also told cats would rarely put much of there paws
in the water. Unless they are more cautious, none of the slower swimming
fantails have any problem. Also as mentioned there are only a few places
that resemble a 'scratch'.
2) I do have some concrete bricks around the side which some of my plants
sit on, but by in large I don't think there are many narrow places for them
to have to squeeze through.
3) I have wondered about parasites, but thus far there are no bacterial
infections and I first notice many of these problems when the water was sub
feeding temperature.
So, any thoughts?
Thanxx
Bill