Stephanie W asked:
i have about 14 koi carp in a pond, they used to be really lively but a couple of weeks ago they stopped coming up top to feed and do not eat anymore. the swim a bit around the pond but not much. two have recently died and there is currently one which is dying. i wonder if anyone can help, or has any tips to save my dying fish, it would be much appreciated.
i have about 14 koi carp in a pond, they used to be really lively but a couple of weeks ago they stopped coming up top to feed and do not eat anymore. the swim a bit around the pond but not much. two have recently died and there is currently one which is dying. i wonder if anyone can help, or has any tips to save my dying fish, it would be much appreciated.
How cold is your water? It is about time for pond fish to start slowing down and going into their pseudo-hibernation, which includes stopping eating. If you continue to feed pond fish when they have slowed down or stopped eating, the food will not get eaten and will, instead, just rot in the water causing it to become toxic and kill fish.
Another related possibility is that, again, it is fall and leaves and other vegetative debris is falling into the pond and rotting, also causing toxic water quality.
The other question is, how large is your pond? For 14 koi, you must have about at least a 1,400 gallon pond. Anything smaller is also going to result in an overabundance of waste resulting in toxic water quality.
But, regardless of HOW, you can see that it all comes down to toxic water quality. You need to get into that pond and clean out every bit of junk and debris on the bottom of the pond and do a major water change; about 50% to 75%, and rinse the filter very well. While ponds will take care of themselves a little better than indoor aquarium tanks will, we are still obligated to watch over them and take care of them when needed. Keep debris out of the water. Don’t overfeed. When the water temperature reaches about 55-50 degrees F, you cut feeding down to about half. When the water temperature reaches around 40 degrees F, you stop feeding entirely.
The number one cause of illness in fish is poor water quality. As soon as your fish begin acting abnormal, that’s always a good clue to check your water parameters. Your ammonia and nitrites should be at zero, with your nitrates at no more than 20 ppm. If you don’t have a good testing kit, I would recommend investing in one. At the very least, you can take some of your pond water down to your local fish store and ask them to test it for you.
If your pond’s water is not testing out as above (zero ammonia, zero nitrites, 20 ppm nitrates), then do a 30-50% water change daily until it does. Be sure to treat the water you replace with a good dechlorinator before putting it in your pond.
Beyond that, I can’t really say what might be going on with your fish without more details on their behavior and appearance. Venice Girl is 100% correct in saying that, as the weather (and the water temps) grow colder, your fish will slow down and go into a pseudo-hibernation. Discontinue feeding when the water temp drops below 50-55 degrees F. However, if you’re noticing flashing or jumping, this could be a sign of parasites (koi are notorious for getting flukes). If you are seeing red lines in the fins and under the skin surface, it could be sepsis (septicemia). If you see an abundance of slime coat on your fish, it could be parasites and/or fungus. If you are seeing bloating, it could be dropsy or a swim bladder problem. It’s just really hard to narrow it down without more details.
However, you can try a shot gun approach – I generally do this at the end of the summer, anyway, to try to send my koi into their winter hibernation state in as good of condition as possible:
1. Feed a medicated food (if they’re still eating) – I like Medikoi.
2. Salt the pond to .3% (.6% if you either don’t have plants, or do but don’t care if they turn yellow and/or die).
3. Treat with Pro-Form C (basically, formalin) and Praziquantel at the same time. Use the real, powdered prazi – not the liquid pseudo Prazi. The Pro-Form will get rid of most every parasite but flukes, and the Prazi is excellent for controlling them. Using the two together does not hurt the fish at all – in fact, the two medicines enhance each other’s effectiveness. Both of these medicines are easily available on-line, and I have even seen them in garden stores and pet shops locally.
The above should take care of most problems you would be likely to have, with the exception of dropsy and sepsis. These are both bacteria-caused illnesses, and if you are seeing signs of either one of these, I recommend treating your entire pond with AP Ponds Anti-bacterial treatment.
As a final note, you might want to check this website: It’s run by a veterinarian who specializes in the care and keeping of koi and goldfish and he has been a lifesaver for me, more than once!
Hope this helps – good luck!