Many Ways To Kill A Fish
Published: Wed, 7 Oct 2015 09:45:02
By: Karen LeFever
Many Ways to Kill Fish
A STORY BY RANDY LEFEVER
They say the best fish keepers are the ones that have killed the most fish. I must be a pretty good fish keeper because I've killed many fish in many different ways in the last 35 years. Below is a story of one such incident.
Several years ago I built a 20,000 gallon koi pond at my house. I researched it thoroughly. I had it all, bottom drains, settling tanks, skimmers, UV, all kinds of filtration. I was going to have the best pond with the best water quality. I seeded the filter with ammonia chloride, and waited for the ammonia and nitrite to zero out. Now I was finally ready for fish. Boy, this was going to be GREAT! The perfect pond with the perfect water. To seal the deal in regards to perfect water quality I plumbed in fresh well water from my house and adjusted the flow so that the pond would have a 10 percent water change every day. So we harvested some three year olds, and I painstakingly picked out five of the best fish I could find. Since I'm a "Koi Professional" I knew what to do. Start slowly, let the filter mature, don't get anxious and start piling fish in there. So in the fish go. They're going to love this. Just five fish in 20,000 gallons in a koi pond with awesome filtration and constant water changes.
After about a week the fish started acting funny, hanging around the top, or lying on the bottom of the the pond. Well I am a "Koi Professional" so this shouldn't be too hard to figure out, after all I've been diagnosing and treating koi for over 35 years. They obviously have parasites or some bacterial infection. So I catch one out, do a scraping, put it under the scope expecting to find a massive infection of Costia or Flukes. And I find nothing. The gills are clean, there's no sign of any sort of bacterial infection. No sores, no bloating, no fin rot, no signs of KHV or SVC. I'm stumped. And embarrassed. I take care of thousands of koi every day, and I can't keep five koi alive in my personal koi pond? Maybe I'm not the "Koi Professional" that I profess to be.
So I send the fish off to Vicky Vaughn at Koi Lab. She calls back the next day and tells me that she has no idea what's killing the fish. Says that it is the cleanest fish she's ever seen. Not one parasite anywhere. She will do a necropsy and get back to me. I re-check the water quality in the pond. Still perfect. Out of frustration
Fish loss is hard.
I double the amount of fresh well water going in. The next day all the koi are dead. By now I'm worried that my fish have some exotic viral disease never seen before. A couple of days later I'm fixing myself a glass of ice water. We have to let the faucet run for a minute or so because the well water we have is acid, and it leeches
the copper from the plumbing in my house. So then it hits me! The water going into the pond runs through the copper plumbing in my house, leaching copper the whole time. I was poisoning my fish! No wonder there were no parasites, the copper was burning them off the fish. When I doubled the flow going in, it doubled the copper and killed the fish overnight.
So I learned at least three valuable lessons. First, no matter what your level of experience or expertise, there's always something more to learn. Secondly, don't always assume some sort of disease or parasite is killing your fish. Third, Copper and koi DO NOT MIX.
Many Ways to Kill A Fish