Pond Salt, Should You Use It?
You may have heard people say that you should add salt to your pond. It may or may not be the best choice for your situation. See what you think after you read this and weigh the pro’s and con’s for yourself before adding pond salt.
Can Freshwater Ponds Benefit from Adding Salt? Possibly
- Salt can help fish by preventing and sometimes curing diseases and parasitic infections. Parasites may also become resist in time, so in the long run- worth it? May be best used as a “salt bath treatment” or in stock tanks.
- Salt may help fish by relieving the stress caused by pathogenic bacteria and poor water conditions.
- Helps fish conserve energy by maintaining osmo-regulation (fluid balance inside their bodies) and may benefit their slime coat
- Can reduce Nitrite toxicity from high Ammonia levels
What Type of Salt is used for Ponds?

There are commercial pond salts you can use and are probably the best choice. Rock salt can be used safely in ponds and is more cost efficient than “pond salt”. Make sure it is pure rock salt and that there are no additives like iodine or yellow prussiate of soda (YPS). We do not use Iodized Salt (regular table salt) in ponds.
How is Salt Applied to Ponds?
The rate at which we add salt varies from up to .1-.3% Salt is added gradually at higher concentrations. For every 1ppt (or .1%) add 1lb of salt (or about a Cup or 1 ¼ cups) per 100 gallons of water. For a 2ppt (or .2% or 2 ½ cups/100 gallons) split up the dose and add it in 3 days. If your pond is 2000 gallons and you want a 2ppt salt concentration, add 40lbs total- about 13-14lbs of salt for the first dose day 1, then repeat on days 2 & 3. This gives fish time to adjust to the saline levels.
How Often should Salt be Added to Ponds?
As water evaporates, the salt concentration increases. When you top off your pond with hose water as the level evaporates, do not add more salt. The only way salt leaves the pond is through water changes or rain overflow. Testing your levels with a salt meter or test strips is the best way to know your salt concentration.
What are Salt Baths?
This is my favorite method to use salt. Fish are captured- either during a cleaning, newly introduced fish or sick fish from the pond- and put into a concentrated salt bath. Prepare the bath with seasoned pond water- about 5-10 gallons inside a tub or bucket. Then add 2 cups salt/ 5 gallons of water. Add fish after salt is dissolved. Monitor the fish the entire time it is in the bath. After about 5-10 minutes, the fish will start to list or float to the side, that is when you take the fish out and return it to the pond or quarantine tank.
Can Salt Effect my Pond Plants?
Salt will affect plants and may damage them if the % or ppt (parts per thousand) is too high. If you use salt during spring and summer, use a lower salt concentration of 1 ppt (or .1%). During fall and winter when plants are dormant (or if you have no plants in your pond) you can use a higher salt concentration of 2-3 ppt (.2-.3%) or if you don’t have fish. Since algae are plants, adding some salt may also help keep your algae in control – a bit anyway.
Are there any Precautions with Adding Salt to my Pond?

Plants can burn and possibly die if levels are too high. The other, most important precaution is when using fish medications in combination with salt . Many fish medications used for disease and parasites may contain formalin, formaldehyde or other active ingredients that do not mix with salt (causing possible damage to fish by burning their gills). It is always best to know what you are treating, why you are treating and if salt can be used in combination. You can easily kill or injure your fish by over treating.
Is it Absolutely Necessary to Add Salt?
No. Some people even advocate against salt- see link below. Others love using salt, I also included a link for this as well. Just note that some parasites may become resistant to salt and once salt is in your pond it is hard to get all of it out. A good complete cleanout will help eliminate salt concentrations.
If you would like to know more about salt and fish care, please visit www.koivet.com I took my fish keeping courses with this veterinarian- Dr. Erik Johnson- he is a wealth of information! https://drjohnson.com/resources-from-garden-state-koi-wet-lab-hosted-at-blue-ridge-fish-hatchery/