I use Pond Salt and have followed the instructions on my salt test kit for amount of salt to add. Recently I did some water changes and we had a lot of rain last week so i checked my salt content and found it to be almost non existent. I had about 3/4 of a container of salt left and added it to my 2000 gallon pond. I should have added much more salt according to the test kit. My local supply store is out of salt until Thursday. I just got my first Newsletter from you and was interested to read what you said about using lower amounts of salt than manufacturers suggest. Would you explain your theory to me? I was going to go to as many places as I had to tomorrow to find salt. Maybe not necessary. Thanks- I hope your ponds are doing better now!

If you look at nature, freshwater ponds normally don't have much salt in them. They also don't have many fish and thus low amounts of fish nasties which include fish parasites, bacteria, funguses, and viruses. Now, in our ornamental ponds, we usually can't help ourselves, and we put a ton of fish in a smaller pond. Due to higher concentrations, those fish nasties also multiple happily.

Sodium chloride (table salt, aquarium salt, pond salt) increases the ion concentration in the water. Inside the fish and fish nasties, there are more ions than in the pond water. When you have two bodies of water next to each other, they want to reach equilibrium which means water will flow from the higher concentration of ions side to the lower concentration side. For the fish and their fish nasties, that means that they must constantly pump water out of their bodies that is flooding into it. That takes work. When we add a little bit of salt to the water, it reduces the work the aquatic animals have to do. They save energy. At some point, the salt gets too high and kills the animals as then there is more salt inside their bodies than in the water, and the water flows out of their bodies, and they dessicate. The fish nasties are more prone to that happening which means that salt will kill many parasites, bacteria, and funguses.

On top of all that, other animals are more sensitive to salt (like the fish nasties are). Those include snails, shrimp, frogs, insect larvae, microorganisms, and even good bacteria. They may all die before the salt concentration is toxic to fish. Then, there are the plants. Plants don't like salt at all. Too much, and they wilt just like the dessicated fish nasties.

So, it's best to add just the amount of salt that helps the fish a little bit, deters the fish nasties, and doesn't harm the sensitive animals and plants. The recommended doses on the pond salt containers may technically be safe for say a healthy goldfish but are they safe for the snails, sensitive fish like orfe, sick fish, frogs, and plants? So, I play it safe and use half as much. If you used no salt, the pond would probably do just fine. If you have soft water like me, then there are fewer natural ions and salts so adding salt becomes more important.

So, don't stress over the salt. The pond will do fine without it at least for now.

Thanks Robyn. Your explanation makes a lot of sense. I was able to get salt yesterdsay but am not going to add it to the pond now. I use it to soak the rocks for reactivation so I'm glad i was able to get it. My pond and fish are doing great. Thanks for all your help!