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If you have a koi, pond or fish problem, this site takes you through twenty easy questions and at the end you know what you need to fix in your pond to create restored Koi health.



Koi Care Rapid Losses In Koi & Goldfish

Obviously "time is of the essence", but that does not obviate the need for immediate water quality testing. When your koi are sick and dying rapdily, my FIRST thought is pond water quality, to include poisoning or derangements with Ammonia, Nitrite, Nitrate, PH and Carbonate Alkalinity. Even issues with carbon dioxide and hydrogen sulfide are possible. However those two parameters are rarer, and much harder to test for.

So, the first steps with rapid losses include pond water testing.

If your pond water quality appears "good", some would recommend a massive water change to remove any possible toxins, reduce bacterial numbers, thin populations of parasites, improve overall water quality including ORP, and more. I would endorse the concept and perform a major water change if it would not seriously alter the ambient temperature of the pond in the 'colder" direction. (Say, mid summer you have to be sort of careful).

If you're concerned that it could be a virus, for example if you've recently added new fish without quarantine and now fish are dying pell mell - consider this article on the Koi Viruses.

Then, salt at 0.3 to 0.6% would be highly recommended. Read on.

If you want to try a shotgun (blanket) regimen that could work well, after the initial water change:

You'd be VERY smart to consider a shotgun remedy for basic diseases, plus superheating, to skate past various parasite, bacterial and KHV (virus) diseases.

Recommendation then:

  1. Feed medicated food for the first 14 days of quarantine
  2. Use salt at 0.3% to 0.6% (safe for all fish) (Salt article)
  3. Use Prazi in case (good chance) there's Flukes on the incoming fish.
  4. Heat for ONE WEEK to 86 degrees Fahrenheit. (Article on heating.)