Copper and Zinc Kill Koi
I'm sure it comes as no surprise to many of you that copper and zinc in the water kills koi. It certainly wasn't news to me. I mean after all, how many stories of copper lined heat exchangers dumping massive amounts of copper in the water and killing all the koi do you have to hear before you get the idea? Probably not many. So before I go any further let me give you some history. I've been keeping koi for a while now. Long enough to keep my koi alive for sure. I can use a microscope and id parasites and treat accordingly. No problem. Here is why: I live in Northern Virginia. I don't heat my pond and every spring I have an outbreak of something. It's like clock work. I scope them or call my good friend REC and he comes over and we look at them and treat accordingly. Yes I started out with a crappy little overstocked water garden but I've upgraded a lot since those days. I've kept the stocking rates down. I do water changes every other day in the summer (really). I dump the settlement on my larger pond every day in the summer. I even do water changes over the winter, not as many obviously but I do them anyway. Both my ponds are overfiltered by at least 2x the manufacturers ratings. Even with all that, every spring its the same thing....Sick koi! This year has been really bad. It started in February when my goshiki floated to the surface dead while doing a water change. She had been treated in September for a strange ulcer she had developed on her gill plate. Scrapes at that time found nothing out of the ordinary. And in case you are wondering the scrape and scope was done by REC (of Koivet) and Terri Janas (KHA). I also looked and found nothing. Anyway it had appeared to be healing going into winter but in December we had a warm snap that caused an algae bloom in that pond that clear until March so I couldn't see them anymore. So long story short the goshiki was death number in 2007. So now its March and I can see the same old problems popping up. I had a toad spawn in both ponds and found flukes on a couple koi and hit both ponds with Prazi. The koi continued to get worse. Scoped again..nothing. Cold snap at the end of March. Warms up again and the toads spawn again. So flukes make sense. Got them once so why not again? Did some scrapes and saw might have been flukes so I hit them again with Prazi. Koi are still getting worse and now I'm treating ulcers. Some are pond koi and they get a pp treatment directly to the ulcer while the show koi get tricide neo dips and Debride cream. I confer with REC and then Terri Janas comes over. We spend the day testing and scraping. We do a pp treatment on both ponds thinking maybe its bacteria in the water. We also do some Baytril injections on some of them. At this point a couple more koi have died. Couldn't tell you which ones as I've lost track of much of this. At this point REC has me do some research on SVC and KHV to see if it looks like it could be either. The symptoms don't match and quite frankly both ponds should have been wiped out at this point if it were either of those. Now let me state at about this point I am ready to fill in the ponds. I've been fighting this problems for months now and I'm quite tired of it. The worst part is you start to question your sanity and koi keeping abilities. Do you know how many times I was asked what my ammonia levels were, if I was overstocked, do I do water changes, is the filter clean? Ok I know thats right of of the koi health 101 book but c'mon don't you think I checked that? Ask me for the levels once and when I give them to you don't ask me if I'm sure (cause I am)(Thank god REC and Terri didn't ask me those questions I think my head would have exploded if they did). So back to the SVC thing. That had me spooked. If I sent a fish in for testing and it came up positive (and was almost sure it wouldn't) then the EPA or somebody would have swooped in and killed all my fish and filled in the ponds. But anyway after MUCH discussion with REC and Terri they finally convinced me to do it. At this point my best koi had died and well, it didn't really matter anymore. BTW all of this is happening in a pond with a rock solid ph of 9.1 but thats another story. So anyway I send a koi and water samples from both ponds and the tap water(well) to Vicki Vaughn at UGA. The results were a mixed blessing. While it turned out it wasn't some weird bacteria or virus or parasite, which meant I wasn't crazy and I actually did know how to use a scope, there was a problem. Turns out there is copper and zinc in my water. Mind you its not nearly enough to be hazardous for human consumption but it is just enough to kill the immune system of koi. So basically any little bacteria (and we are surrounded by bacteria all the time) will make my koi sick and eventually kill them. Doesn't matter what I treat them with. I can use antibiotic shots, antibiotic dips, antibiotic pastes, antibiotic foods and it will not matter. With no immune system they will never heal. No where do I go from here. Well at the moment I treated the ponds with Novaqua. It binds to the heavy metals and makes them harmless. I also am going to start doing water changes with it until I can get some Poly-filter pads in. These are toxic metal sponges basically. For the long term I will be looking at ways to filter to more permanently filter the water. First though I will have to determine if its the pipes in the house or if its coming from the well that way. So another test is needed but in the meantime I will use Novaqua and the pads (when they get here). Ok since this is my website there have to be pictures so of course I have some.
Jim North
Note from Terri Janas:
As a recent KHA graduate, I want to
thank Jim for giving me this opportunity to help, follow along and expand my
knowledge. Also a huge thanks to Richard Carlson for following along on the
scene, behind the scenes, and for his incredible support. I learned a great deal
from all of this combined. Needless to say we were all stunned to hear that
toxic metals is causing what was occurring. We checked out everything and found
nothing that would warrant what we were seeing. All that was left was to test a
fish and the water. Huge Kudos to Jim for sending in a fish which is firstly
heart wrenching as well as, time consuming and costs money. The waiting for the
results takes patience too while you watch your unhappy Koi at home. The amount
of copper and zinc which is safe for human consumption is much lower for fish we
have learned. The levels of these metals in Jim's pond were low but high enough
to suppress the Koi's immunity. In all our ponds we have parasites and
pathogens. The Koi's slime coat contains a bactericide to defend the skin and in
most cases is enough to protect it. But when they have been stressed like in
transporting, temperature changes, their immunity lessons and they become more
susceptible to pathogens taking hold. Often just changing the environment, less
stress, good water, is all that is needed for the Koi to heal without any
intervention. But toxic metals don't work that way. Even on good days for the
Koi, the metals are there harming them. Jim is on well water and he has never
needed to use a dechlorinator with water changes. We have since learned that
Sodium Thiosulphate (ST) binds toxic metals rendering them harmless. ST is also
found in many dechlorinators like Novaqua and Prime. It can be used in its raw
state, usually crystals. Hence, my feeling now is it might not be a bad idea for
all of those on well water or who have copper pipes, to throw in some ST
crystals when doing a water change, just to be safe. It is cheap enough and
really can't be overdosed. Better yet, get your water tested every few years. It
is certainly worth the money and something I plan on doing myself. The address
to do this can be found at http://www.koilab.com
Terri Janas
AKCA KHA 07
Click here for Water Sample Report
Acceptable levels of copper and zinc:
Copper less then .006 ppm
Zinc less then .005 ppm
WARNING!! Graphic photos of dead koi below. Go no further if you don't want to see dead koi with ulcers.
First up is a series on my most favorite koi. It was a sad day when she died.
See anything wrong with her?
Look closer...
Treated her and put her. Not sure
anymore how long it was between photos so here she is again getting a Tricide
Neo dip. Notice she isn't getting better.
In fact she is getting worse....tail
tube area
Finally after a couple of months of
treatment and moving her to my q tank to escape the "bugs"(oh thats right it was
the water, the same water that was in the qt) she finally died. We tried
progressively stronger antibiotics on her but with no immune system it didn't
matter. She fought til the end though....
Here is another one I lost. Look how deep
that ulcer was...
Here is the koi I sent to UGA. Nothing was
found to be wrong with this fish other then some bacteria that should not have
caused it any problems.
No problems with the gills either.
Wondering how to spot an ulcer before it
gets nasty? Take a look at these pics. The first koi now has an ulcer the size
of a half dollar in the circled area. The other koi actually healed
Thats all for now on this subject. I'll add some links to some discussions on this at a later date.