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Symptoms Finder

You'll get a picture of the koi/goldfish, you click on the koi fish where it's sick, or choose from several other behavioral options that your koi may be exhibiting.

What KoiCrisis Is For?

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We offer FREE personal help with your sick fish and/or pond water quality problem. Fill out our easy “Help Form” by Aqua Meds

Feeding Koi

What to feed?
What not to feed?
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Aqua Meds®

Have questions about care of sick fish and/or pond water quality problems and how to treat them? We have the answers.

Fish Medicines

Learn about fish medicines, what they do, and where to get them.


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.



Deadly Koi Pond pH Crash

Koi Pond pH Crash

PH is only a measurement of the free Hydrogen ions in your pond water and is very, very dynamic. Your koi pond pH can change overnight...In particular, your pond pH is prone to fall, and "crashes" are quick, and fatal. Interestingly, many people say they checked their pond pH last week, and are surprised to find that the pH can change overnight.

In simple terms, the pH in your pond water is supported in range by the carbonate activity of the water (measured in Total Alkalinity) and when the carbonates are exhausted, or overloaded, pond pH plummets to 5.5 and kills filter bacteria and and your koi. In other situations, your pond pH can glide downward very slowly over months and thus your resident koi can survive a low pond pH but the new koi you keep buying perish quickly as they enter pond water with a very acid pH.

Check your pond pH regularly, and also, to get a grip on your 'safety net', measure the water's "Carbonate Hardness" (KH) activity often.

Buy carbonates for the pond in a sensibly priced pH Buffer.