Should You Add Salt to Freshwater Aquariums, and 1 Benefit.

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Keeping fishy pets may seem simple at first but it involves a lot more than just dumping a fish and some tap water in a tank and watching them swim around.


You have to do water changes and monitor your fish’s health.

Freshwater aquariums are easier because you don’t have to deal with adding salt to the water of a tropical tank.

However, at some point, you will probably have to add salt to your aquarium to treat certain illnesses in your fish. So naturally, you are going to figure out how much salt to add…

When adding salt to your freshwater aquarium, you should start with the lowest dose possible for the disease or illness you are trying to treat. You can gradually add more if needed. Always follow the manufacturer’s recommended dosage for Salts Specifically For Freshwater Fish.

How To Properly Add Salt To Your Freshwater Aquarium

AquariumSalt PetAquariums Should You Add Salt to Freshwater Aquariums, and 1 Benefit.

When adding salt to your aquarium you want to find a finer grain of salt that will dissolve easier in the water versus like a rock salt that will take too long and may not completely dissolve.

You also want to dissolve the salt in a separate container because if you try to add it to your aquarium, your fish may ingest a large amount which can screw them up even worse and you are already trying to treat something wrong with them.

If they ingest a large amount of salt, you are just adding to your problems.

Benefits Of Adding Salt To Your Freshwater Aquarium

Salt is not a part of regular maintenance for a freshwater aquarium.

For tropical aquariums, you have to add salt to the water because the fish are from oceans which have saltwater but freshwater fish are from lakes or inland water which doesn’t have salt.

However salt is great for treating bacterial, fungal, and parasitic infections in your fish.

You can use it with medications or try salt alone to treat these infections.

Some people prefer to use salt first because it is cheaper than medication and easy to get.

Salts are a natural treatment while many of the medications have chemicals that may do more harm than good to your fish. Whenever you have an aquarium, it is a good rule of thumb to never let any chemicals enter the water if possible.

How To Use Salts In Your Freshwater Aquarium

The most common use for salts in freshwater is to treat fish for parasites that are attached to the outside of the fish.

Ich, costia, and anchor worms are the most frequent parasites that infect fish.

For these parasites, you can’t mess around. You need close to 1 and a half cups of salt per 10 gallons.

You can use a hydrometer to measure the specific gravity of your saltwater mixture which should be between 1.005 and 1.009 or 7 – 13 ppt. for 3 weeks. Not all freshwater fish can handle this much salt so make sure you gradually increase the amount of salt.

The key to using salts in your freshwater aquarium is to catch the infection early.

The most common dosage is one tablespoon for every 5 gallons but if you get salts specifically for aquariums, you will follow the directions that come with them anyways.

Salt Bath – usually one teaspoon of salt per gallon of water for 3-4 weeks with weekly water changes of at least 25% to gradually get rid of the salt so you don’t shock your fish.

Salt Dip – Dips are reserved for severe parasitic infections. You dissolve 5 tablespoons per gallon of water in a container separate from your aquarium. Place your fish in the container for 5 – 30 minutes depending on if they are acting weird or not like laying on their side.

If they are acting weird, just put them back in the aquarium.

It can get confusing because there are a lot of salts available for use but the most common salts for freshwater fish diseases are:

  • Sodium Chloride(Aquarium Salt)
  • Magnesium Sulfate(Epsom Salt)

Aquarium salt can help replenish electrolytes and is great for parasitic, fungal, and bacterial infections.

Epsom salt is more of a laxative and muscle relaxer that is used for fish that are egg-bound, dropsy, and have swim bladder problems or digestive issues.

When you get Epsom salt, make sure it is pure with absolutely no additives.

In other words, don’t buy bath salts when it comes to Epsom salts, make sure it is for fish.

There are other salts available to use but they may have stuff added to them. It is better to get salts that are specifically for aquarium fish.


The key to using aquarium salts properly is to follow the manufacturer’s directions and remember to start with the lowest recommended dosage.

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Pet Aquariums

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