Pond Health Related Questions
Pond test kits show up levels of fish waste in the water: Ammonia, Nitrite and Nitrate, all of which are detrimental to the fish and in the case of Ammonia and Nitrite can be fatal at high levels. Because these substances are all dissolved in the water they are not visible and it is quite possible to have water that is clear and appears clean but which is extremely unhealthy for your fish.
½ ounce per US gallon is the standard rate to use salt for support in the treatment of ulcers, fin rot and some parasite problems. This can be increased over a 3-day period to a level of 1 ounce per US gallon when fish are suffering from large ulcers. The salt should be removed with a series of water changes after the treatment is finished.
Koi are fresh water fish and while a low level of salt may not appear to cause any problems, it is better to keep your fish In fresh water, unless using salt for a specific problem such as the treatment of ulcers.
No, most medications have undesirable side effects such as reduction of oxygen level or killing some of the filter bacteria. Your koi should only be subjected to these effects if there is a specific disease problem in the pond that poses more of a risk to their health. Even then it is important to ensure the water quality is correct and to identify the cause of the problem before commencing any treatment.
Poor water quality kills more koi than any disease and testing the water parameters should always be the first step if your fish are unwell.