I have a thousand gallon preformed pond with gold fish. I lost 8 large and seemingly healthy fish during this summer. We had some triple digit temperature days so could this have caused the kill? I have the pond covered with water hyacinth and water lily but it it is the direct sun. Could there have been too much hyacinth as they do reproduce profusely. Any feedback would be appreciated. Thanks Sharon Curtis
The cause of fish death during very hot temperatures is usually caused by a lack of oxygen (the hotter the water, the less dissolved oxygen it holds). It is very important to add oxygen either with a waterfall, a fountain or an air pump.
Your Water Hyacinths actually help shade the pond and keep it cooler.