Pond fish dying in hot weather? "Fix it Now"

Pond fish dying in hot weather? "Fix it Now"


 Why any one of these things can cause major problems in your pond over summer

  Fully stocked pond

  Big Koi   

  Poor quality food 

  Lack of Beneficial bacteria  

  Shallow pond less than 40cm in full sun

  Murky water

  No water movement 


 high ambient temperature

 low pH

 high phosphate levels in the pond water

How to Oxygenate a pond quickly "fix it"

Temperature- Warm water loses its capacity to hold onto oxygen particularly at temperatures above 29 degrees Celsius. Warm water combined with poor water circulation can create pockets of oxygen-depleted water harmful to pond inhabitants.


For a shallow pond in full sun drape or fix shade cloth over the pond & add an extra pump for more water movement.

Biological load- Simply put, more pond inhabitants mean greater demand for oxygen. Poor quality food will cause more phosphates & organic material within the pond to complete the process of breaking down organic waste good bacteria needs oxygen, heavily stocked ponds can deplete the existing oxygen supply.


 Do a water change 20% at least daily in extremely hot weather and weekly in temps up to 30 degrees. 

                           Always feed hi quality food, to keep your water at its best, and no phosphates fish food

 Test your pH and Phosphate levels

TEST pH regulates how much oxygen is available to your fish, a pH of 7-5 to 7-8 is preferred for pond fish. 

TEST Phosphate levels are directly related to the pollution in your pond, when they are too high your pond wont be stable, you may have dirty water, sludge on the bottom, algae, green water, debris floating on the water surface, dying plants, dying fish. 10.mg/1 is the highest level that is expected in a backyard pond. 


If the pH is below 7-5 bring it up slowly over the next week with pH up in liquid form or bi carb from the supermarket. Bi Carb dose is grams per 1000ltrs to 5000ltrs if your pond is bigger than 5000ltrs text or email the hatchery for the dose. Test daily till you have the correct pH by adding bi carb in the morning and testing the next morning.

FIX IT phosphate

Do a water change of up to 50% depending on the amount of phosphate in the water. for more information on understanding test results email the hatchery. Test kits

Water Clarity- dark, murky or turbid water can limit the ability of plants to photosynthesize & generate oxygen.


Maintain clear water for healthy plant growth essential for natural oxygen production. Use clear water product.


Surface exchange - Encourage proper gas exchange by keeping an area of open water. This open area should be free of vegetation so surface water is exposed to fresh air.

Mixing - Water turbulence of any kind, regardless of how it's generated, significantly increases gas exchange. The fastest, easiest way to raise the oxygen level in your pond is a water change or with an aerator, fountain, or waterfall.

Windsor fish hatchery koi and goldfish farm selling fish to you online www.windsorfishhatchery.com.au


Windsor fish hatchery breeding and selling Koi & Goldfish since 1984