| Koi with skin problems
Hi,
I have three koi with skin problems which I hope someone can shed some light on. The are all sanke line but from different lines as far as I know. I have shown photos of two of them here.
One is a 60cm female "kohaku" (the one with shimmies that you can see) and the other is a 55cm female sanke. I have had both fish in my possession for 5 years plus and both fish are at least 6 years old.
The kohaku skin deterioration has been "in progress" for 4 years but I have never got around to doing anything about it because I figured it was carp pox and I've not had any success dealing with that before. When the problem first started it was evident only in winter (water temp ranging from 10C/50F to 18C/65F) and in summer it would disappear completely (water temp range 22C/72F to 30C/86F), only to return in winter again. Now it improves in summer but never completely disappears, and is getting pretty bad now, as you can see (water temp circa 20C/68F). The problems only appear on the body, not the head. As you can see hopefully the problem areas are "raised" above the rest of the normal skin.
The sanke has only just started having problems and they are barely visible in the photo. The problems only appear on the head, not the body so I'm not sure if they are related to the kohaku's problems. They are below the skin so if you wipe the area with your finger nothing changes. They appear as very slight lightening of the hi to a yellower or whiter tone. The other sanke (a male) (which is not pictured here) also has problems on the head which look similar to this one, having only just started.
The pond is 25,000L in a full sun position but with a shade cloth sail providing some sun protection during summer. In autumn (it's mid autumn now where I live) I remove this shade to keep the water temperature up a bit. The pond has 10 fish average size 50cm in it. Any suggestions/diagnosis would be greatly appreciated.
thanks, Richard |