Proper Salinity Level

What Amount of Salt Do I Need?

The salinity level in your pond is your health care plan for your fish. It is your Koi’s natural antibody. The proper amount of salt in the pond allows for a healthy slime coat to be formed on the fish’s scales. This slime coat protects the fish from parasites as well as bacteria that could be harmful. However, since Koi are fresh water fish, to much salt could kill them. We recommend keeping your salt level at 0.1% for the best results.

The salt level of your pond should be tested when the pond is first set up and whenever a water change is made. Since salt does not evaporate as water does, salt only needs to be added when water is pumped from the pond.

Ideal Salinity: 0.1% - 0.25%
Acceptable Range: 0.1% - 0.25%

A minimum for one pound (2 cups) of Salt to a maximum of 2.5 pounds (5 Cups) per 100 Gallons (.1 to .25%) of water should be added to your pond. Salt is essential for fish health. It control disease, helps enhance slime coat and reduces the stress on your fish. Salt in the pond should not exceed 2.5 pounds per 100 gallons (.25%) because it may harm the water plants beyond that level. New studies have indicated that keeping your salt level between .2% and .25% will reduce the growth of string algae.

The only exception to this is if you have a pond filled with sick fish. If this is the case you will need to remove the plants you wish to save and increase the salt content to 3 pounds per 100 gallons or .3%. If only a few fish are sick and you are able to catch the fish, we recommend setting up a quarantine tank. In the quarantine tank, the salt level should be at three pounds per 100 gallons (.3%) at a minimum. With very sick fish you can go up to 6 pounds per 100 gallons or .6% salt. When setting up a quarantine tank, start with .3% on “Day 1” and increase the salt content .1% per day for the next three day, to a maximum of .6% salt. When working with high levels of salt a salinity meter is recommended to ensure an accurate salt level.

If you are adding water to your pond due to water evaporation, DO NOT add salt, salt does not evaporate. However, when performing a water change, add new salt based on the amount of water replaced, not the total volume of the pond. Ideally, you should be using a salinity meter to monitor the salt level in your pond.