Keeping Your Fish Safe in Hot Weather

Koi are happiest in water temperatures between 59 and 78 degrees. Of course they survive in our ponds in the winter in much colder water and they should be able to handle water warmer than 78 degrees if we give them some help.

High water temperatures are a problem because the warmer the water gets the less dissolved oxygen there is in the water.

Ammonia becomes more toxic as water warms and the higher your PH is in the pond.Here are some simple steps to help your fish through the heat wave:

Provide shade.

Hyacinth and Lettuce plants, big beautiful water lilies or other aquatic plants. A carefully aimed patio umbrella, or simply floating a pool toy in the pond. Pond dye will darken the water and allow less light to enter the water.

Provide Oxygen.

Turn up your pump if you can to provide more vigorous waterfalls. Add an aerator or an extra pump to splash more water. Ensure that your pumps run all night, don’t turn them off!

Reducing water temperature – methods

Reduce the water temperature by doing a partial water change. Pump out some of the warm water from the pond and put fresh cooler water in. If you do this you must ensure that you dechlorinate the water!

The hotter the day the more chlorine our municipalities put in the water supply, so it is vital that you dechlorinate before adding the new water. Dechlorinator is added before you add the freshwater, not after you’ve filled the pond.

Reduce or eliminate food to reduce ammonia

Reduce or eliminate the amount of food you feed to help reduce ammonia. As we mentioned ammonia is more toxic at higher temperatures and higher PH, so stop feeding to help reduce the ammonia. Fish go months barely eating in the winter, so they can go three days through a heat event without any problems.

DO NOT USE algaecides in this heat! Algaecides reduce the amount of dissolved oxygen in the water. You will kill fish using it now.

Expect more algae in your pond in the warm weather. Algae does not harm your fish it is just unsightly.

Falling Water Gardens is open seven days a week from 10am until 6pm. We have all the plants you need to add extra shade and dechlorinator to allow you to make cooling water changes. Come in to get what you need.