Aquarium Salt: When and How to Use It Properly

Is it safe to use freshwater salt in aquarium salt? Some people recommend dosing it all the time to provide fish with essential electrolytes, while others say it’s mostly used for treating diseases. After years of testing with hundreds of fish, we’ve witnessed the true power of salt. NaCl (Sodium Chloride) is an all-purpose “medication” that works against bacteria, yeast, and parasites. It is inexpensive and readily available in all parts of the world. You can use it in low or high concentrations.

However, the reason why we typically recommend our trio of medications to beginners is because different kinds of fish have different tolerance levels to salt, and it can be hard to figure out and remember the correct dosage for each species. Salt can’t be used with most living plants and snails. It is possible to accidentally overdose salt which can kill all the bacteria in your freshwater aquarium. Both novice and experienced fish keepers will benefit from this highly effective remedy if they use accurate measurements and are careful with their usage.

How Does Aquarium Salt Work?

Salt essentially causes death by dehydration. By raising the salinity of the aquarium water, water is sucked out of the bacteria, fungus, or parasite as osmosis seeks to balance the salt concentration on each side of its membrane or skin. Because the fish have more water and mass, these microorganisms are more likely to die than their hosts. Some microorganisms are capable of surviving higher levels of salt, so salt is not an all-purpose bulletproof solution.

Through the power of osmosis, aquarium salt is able to eliminate many pathogens and parasites on fish.

Do I need to use salt all the time?

No, sodium chloride salt should not be used on a daily basis as a preventative measure or health booster. This would be similar to a healthy person taking antibiotics every day in an effort to reduce the risk of infection. Eventually, a superbug could emerge that is resistant to antibiotics and your options for treatment are severely limited. Any fish disease that reaches beyond your “salt barrier”, will require a higher salt concentration to cure. This could be harmful to the fish. Salt can be a powerful tool that you add to your arsenal if it is used sparingly and only when absolutely necessary.

How to Use Salt as a Medication

Salt comes in many sizes and chemical compositions. For this article, however, we are using NaCl rock salt or aquarium salt. This is not table salt, sea salt, or Epsom sodium. (Also note that the measurements below refer to the United States (US), customary units. They do not reflect the UK imperial systems. Our method of treatment starts with the lowest level of salt and gradually increases if the symptoms persist.

Salt comes in many sizes and forms, so make sure to use aquarium salt to follow our treatment regimen.

Level 1 Treatment

1 Tbsp Salt per 3 Gallons of Water

Add 1 tablespoon (Tbsp) of salt per 3 gallons of water. Salt can be added directly to the aquarium or hospital tank. Others prefer to dissolve the salt in small amounts of water. This salt level is similar to Neosporin topical cream for small cuts (in other words it’s not very powerful). It is used to treat mild cases of fungal and bacterial infection. It also gently irritates fish’s slime, causing them to make more beneficial mucus. This can help prevent parasites and other microorganisms getting into their bodies.

We have sold thousands upon thousands of fish from our fish shop. This level of salt is safe to eat , except anchor catfish. The salt solution should be kept in the fish for at least 4 to 5 days. If there is no improvement, increase the concentration.

Level 2 Treatment

1 Tbsp salt per 2 Gallons Water

The next level of treatment requires a salt concentration of 1 Tbsp per 2 gallons. Level 2 can treat a greater number of illnesses. For example, this recipe can be used for treating ich (also known as white spots disease), for a duration of 10 days. However, if the symptoms are only getting worse after 5 days, try increasing the concentration again.

Level 3 Treatment

1 Tbsp Salt for 1 Gallon of water

If medications and lower salt levels don’t work, it’s time for the big guns. This powerful solution will eliminate almost everything if the salt concentration is increased to 1 Tbsp per gallon. Level 3 treatment can be very difficult for scaleless fish and sensitive species. Make sure you do your research. Rasboras are salt-tolerant, as well as tetras and silver dollars, ranios, tetras and livebearers. Even Neocaridina cherry shrimp are quite hardy in salt, but we haven’t done much testing on Caridina crystal shrimp yet.

Note: aquarium salt does not evaporate or get filtered out. As water evaporates, the salt is left behind. Therefore, only add salt (in the proportionate amount) when doing water changes. For instance, if you’re treating 100 gallons of water at level 2 for ich, you need 50 Tbsp of salt initially. Then, if you have to do a 20% water change (or change out 20 gallons of water), add back in 20% of the salt (or 10 Tbsp of salt) to the new water to maintain the same concentration. You should be careful about measuring salt as it is easy to overdose and salt doesn’t break down over time, unlike many medications.

Salt doesn’t evaporate or disappear unless the water it was dissolved in is removed. Be careful not to overdose your aquarium.

How long should salt treatment last?

Keep the salt in the aquarium till the fish is healthy. Then, do water changes to remove the salt.

After treatment is complete, perform a 30% water change with no salt addition. Then wait for a week to observe. – Repeat the 30% water change but do not replace the salt. If the disease does not return, wait another week. – If the disease returns, dose back to the original salt concentration and add a little more salt to increase the solution strength. It is possible that the original salt concentration wasn’t sufficient to eradicate the disease. Or, the fish didn’t spend enough time in the salt solution dehydrating all pathogens.

Can I use salt in place of fish in Quarantine

Yes, it is possible to treat new fish with the level 1 low sodium dosage for two weeks. This will eliminate roughly 60% of all possible diseases. You can also use this technique for healing any fish that got beat up and needs some solitary recovery time in a hospital tank.

Although it may seem easy to grab a packet of fish medication, salt is amazing because of its ability treat mysterious diseases that are difficult to diagnose. To reduce risk to the environment and human health, some countries have begun to ban the sale of antibiotics in the pet trade. In the future aquarium salt could become your best friend for treating sick fish.