What is “Aeromonas Alley”?

Published on September 1, 2011

aeromonas_alley Every year fish in “cold climate” ponds struggle through extreme stress and, in some cases, die due to “Aeromonas Alley.”

**What is “Aeromonas Alley”?**

“Aeromonas Alley” is defined as when your pond water temperature ranges between 42°F and 62°F. Between these temperatures, the deadly “Aeromonas/Pseudomonas” (AP) bacteria grow much faster than your fish’s weak immune system. This makes it very difficult for your koi to fight off this deadly bacterial attack, causing ulcers, fin rot and more. In fact (AP) remains strong throughout the warm summer months. That’s why it’s so important to keep the numbers of (AP) as low as possible in your pond water.

Also beware of “Aeromonas Alley” in the fall when your koi pond water starts dropping below 65°F. At 65°F the immune system of your koi and pond fish starts to decline and weaken. By the time your pond water temperature drops to 60°F the immune system of your koi and pond fish is operating at less than 50% efficiency. However, the deadly (AP) bacteria is still strong and active and takes this opportunity to make their deadly attack on your weaken koi and pond fish.

(To give your fish the protection they need to fight off “Aeromonas Alley” please visit: aquameds.com, click on medications then Aqua MedZyme Dry.)

HNA Ad 2026

Leave a Comment

Your email address will not be published. Required fields are marked *

More Articles

Introducing the AquaMax Eco Titanium Pond Pump

Atlantic-Oase introduces the newest pump in the Pulse 6 line, the AquaMax Eco ...

Inside a 360-Degree Koi Pond Environment

In Friendswood, Texas, what began as a pond renovation quickly evolved into one ...

July / August 2026

The Spaces We Create One of the things I enjoy most about putting ...

Show Us Your Trophies!: Congrats to our 2025 Water Artisans of the Year

From all of us here at POND Trade Magazine, we appreciate everyone who ...
Scroll to Top