As befits the bad karma I am enduring, I am suffering the agony of sick fish.
One of my nerdier pursuits growing up (there were many) was keeping tropical fish. From that experience, I knew that keeping fish was a challenge. A river is a true miracle. It somehow keeps things in balance and fish happily survive. But I thought koi were going to be easier. Koi are a type of carp, and carp inhabit the most fetid streams and pools. Not mine it seems. (Not that the 8000 litre beautiful pond I have is a fetid stream - all water tests are good).
The first sign of trouble was flashing. Flashing is when a fish darts up to a surface and does a rapid turn trying to scratch an itch. It flashes its underbelly and hence the term. So I thought, mmm, I recognise this. My tropical fish once had white spot. Quick treatment should do the trick.
A short while later one fish died. Another developed dropsy. While I have been working crazy hours, I have been reading bits and pieces on the net, and the news was not good - dropsy is always fatal.
But I chose to persevere. My reading told me that salt was the treatment of choice. Which is good, because there are a million medicines at inflated prices in most fish shops. The fish responded well and started looking normal - with the exception of some ulcerated patches.
I treated the water with potassium permanganate - a dangerous affair, as overdosing kills gill tissue and fish die from suffocation.
After a week of good progress things regressed again. I tried Methylene Blue to treat the ulcers which had now spread to two other fish - including one of my big guys - a fish of about 35cm.
And now a week later, the big guy's ulcer is looking suspciously like "hole in the head" - a horrendous condition that literally results in holes appearing in the affected fish's head.
I did another potassium permanganate treatment tonight - together with a concentrated salt and potassium bath. Sadly, the poor guy that started the trouble with dropsy is looking worse for wear - I think the potassium was just too much for his overloaded system.
I am a little suspicious of the shop I bought my fish from. They all come from the same place. It is the biggest koi dealer in Johannesburg. When buying there, I also noticed two of their fish had fin rot. Of course, this hasn't been bad for them - I've probably spent as much on medication as the few thousand I spent on the fish.
Right now I'm thinking of getting an expert koi keeper in - I don't have time to deal with all of this now. And my koi were supposed to relax me...
Some useful koi links:
FishDoc - The home of fish health
A summarised guide to koi disease and treatment
An excellent guide to treating Koi - with videos
Koi Carp - the world's best selling Koi magazine
My biggest, healthiest koi - OJ - about 40cm.