The use of 1 teaspoon of regular rock salt per gallon of aquarium water will do wonders for your fish. It’s a sort of magic elixer for sluggish fish, it will cure or prevent most fish ailments, and I believe it helps the fish grow faster, and “live long and prosper”. If your fish is really sick then I suggest adding another teaspoon of salt to make it 2 teaspoons per gallon. Salt works its magic in 3 ways, 1. parasites and other undesirables in the aquarium are adversely affected by salt, so it is a treatment and preventative for parasites. 2. Wounds heal faster with salt in the water (ever notice how sores heal faster after you swin in the ocean?) and 3. Fish being in water all day have a stressful time trying to keep the right amount of liquid in their body, salt helps the fish in this battle (liken this to the wrinkles you get after a long bath)
Suppose you have an 10 gallon aquarium and you put 5 gallons of fresh-water into it, now if you add 5 gallons of marine (ocean) water you wouldn’t have 5 gallons of salt water and 5 gallons of fresh-water. You would have 10 gallons of brackish water. What happens is that the fresh and saltly water mixes. Alright, suppose you had bag of fresh-water that was semi-porus, and you put it into an aquarium full of saltwater. If you left the bag in there overnight and took the bag out and tasted the water you would find that it turned into salty water, how salty would depend on how porus the bag was. But the point is that a fishes skin is a porus membrane. So if a fish is swimming around in a completly saltless aquarium, and the fishes somewhat salty blood and body fluids are contained in a porus membrane (fish skin) then the fish has to fight to maintain the proper chemistry within it’s own body. Naturally increasing the salt content of the water toward the same level that is within the fishes body will relieve some of the pressure involved in this process, and make life easier for the fish. This same principal holds true in reverse for saltwater fish. So the conclusion is that a teaspoon of salt per gallon will help a freshwater fish, and a less than normal salt concentration will help a saltwater fish.
When using rock salt you don’t have to worry about it being “iodized” or not, theres not enough iodine to really make any difference, and iodine is a trace element found in most natural water anyway.
There are no freshwater fish that are harmed in any way by the addition of 1 teaspoon of salt per gallon. I have never experienced any problem with plants and low salt concentrations, I would quess that 90% of all aquarium plants are not affected by 1 teaspoon of salt per gallon, nor are snails, shrimp, African frogs, Daphnia , nor any and all fish including Catfish, not even Corydoras.
How much (how little) is 1 level teaspoon per gallon?
1 teaspoon = .13% of a gallon
2 teaspoons = .26% of a gallon
3 teaspoons = .39% of a gallon – also = 1 tablespoon
4 teaspoons = .52% of a gallon
8 teaspoons = 1.04% of a gallon
So it takes 24 teaspoons of salt per gallon to make a 3% medicinal saltwater dip solution.
Or to make it easier to understand, it takes approximately 770 teaspoons to equal a gallon
The usual arguments against salt are that “My fish do fine without any salt in the water” , to which I would say, good! but they will do better with salt in the water. I do fine without seatbelts too, unless I need them.
The use of salt and/or a copper based fish medicine such as “Had-A-Snail” or “Aquaisol” will cure or prevent just about all treatable fish diseases.
Note: The use of salt for disease prevention and cure is a greatly debated subject on our message board. I personally believe in it’s magic, but many people disagree.