We may earn commission as an affiliate from qualifying purchase made through any of the link in this post thank you so much.
Is aquarium salt the same as sea salt? I’m sure many of you have heard that aquarium salt is the same as sea salt, which makes it a valuable tool when your fish-friends get sick.
If you’re new to aquarium keeping than one of the questions which may have crossed your mind at some point is aquarium salt: should I use it? Will it help my fish live longer? Well, let’s find out if aquarium salt is it the same as sea salt and will it help your fish?
But how accurate is this information? And what exactly are the benefits of using a soft water treatment like aquarium salt? It is safe to say at this point in time that the aquarium world has been blessed with the emergence of a great many new products over the years.
Additionally, many of these offerings have had their own share of criticism, praise and sometimes both. One such subject matter is the particular topic of salt for marine tanks.
So are you a fish owner? Are you wondering about the difference between aquarium salt, sea salt and regular table salt? Or which one to use? If so then you’re in the right place because this article covers all of these points.
Let’s face it, sea salt can be quite expensive. The price difference can be as little as $2 or as much as $11 per pound (USD). Whether you’re a fish enthusiast, keep a saltwater aquarium.
Or just have your own garden with house plants you might have come across the need for aquarium salt or sea salt. It’s actually a lot easier to tell them apart than you may think.

Is aquarium salt the same as sea salt?
Aquarium and sea salts are not the same. Aquarium salt is made up of sodium chloride, whereas sea salt is made up of sodium chloride and other minerals. The sodium chloride (NaCl) found in aquarium salt is the same substance that makes up table salt.
It’s an ionic compound made up of positively charged sodium ions and negatively charged chloride ions. The addition of other minerals to aquarium salt can make it harder for fish to absorb the sodium chloride, which means they may not be as healthy as they could be.
Sea salt contains many different mineral compounds, including sulfates and chlorides. Sea salts also contain some trace amounts of organic compounds like urea and amino acids.
These organic compounds can cause problems if they get into your aquarium water because they can kill beneficial bacteria needed by your fish to digest food properly.
If you want to treat your aquarium with something besides plain water or dechlorinated tap water, use de-ionized or reverse-osmosis water instead of regular tap water or bottled spring water.
Sea salt is harvested from evaporated seawater. It contains many minerals and elements that are beneficial for humans and animals alike. Sea salt contains magnesium, potassium, calcium, iron, copper and zinc.
Aquariums do not contain these minerals and elements so they must be added separately through the addition of aquarium salt or other additives.
Aquarium salt is made up of sodium chloride (NaCl), magnesium chloride (MgCl2), potassium chloride (KCl), calcium chloride (CaCl2) and sometimes strontium chloride (SrCl2). These ingredients help replenish ions in the water so it can retain its salinity levels.
Key takeaway
- Aquarium salt vs table salt difference
- What is aquarium salt made of?
- Can I use table salt instead of aquarium salt?
- How much aquarium salt per litre

Aquarium salt vs table salt difference
The main difference between the two is that table salt has iodine added to it while aquarium salt does not have iodine added. This means that table salt can be harmful for your fish if used in an aquarium. This is because the iodine present in table salt will kill your fish’s gills and skin if they come into contact with it.
Another difference between the two salts is their density; table salt has a higher density than aquarium salt which makes it heavier than aquarium salt. When you add water to aquarium salt, its density becomes less than that of water and therefore floats on top of the water surface without mixing with it.
On the other hand, when you add water to table salt, its density becomes greater than that of water and therefore sinks down into the water surface without mixing with it.
Table salt is mined from underground deposits of rock salt, while aquarium salt is produced by evaporating seawater in large solar powered evaporation ponds. The resulting water is extremely concentrated with minerals and other trace elements, which is why it works so well for treating disease in fish.
Aquarium salts have been developed specifically for marine applications, so they contain less iodine than table salts do. This is important because iodine can be toxic to some invertebrates such as shrimp or crabs in an aquarium environment.
Aquarium salts also contain several trace elements that are useful for plant growth and overall health such as iron and boron, but these elements aren’t present in table salt at all.
Aquarium salt and table salt are both sodium chloride, but they are different in many ways. Most importantly, aquarium salt is formulated to maintain the specific gravity of water at a level that promotes fish health.
Aquarium salt also contains other minerals and elements, such as magnesium, calcium, potassium and strontium, which are necessary for fish health. Table salt does not contain these other minerals. Instead, table salt is often iodized to prevent goiter (a swelling of the thyroid gland).
The iodine in table salt can be harmful to fish when used in high concentrations or over prolonged periods of time. Aquarium salt may also be referred to as marine salt because it is used to replenish ions lost during evaporation in marine tanks.
However, this is not technically accurate since marine tanks do not evaporate water; they only lose small amounts of water through evaporation from the surface of their water bowls or from the tank itself when power is lost (such as during a blackout).

What is aquarium salt made of?
Aquarium salt is a mineral supplement that adds chemicals essential to fish and other aquatic animals. It’s also called marine salt or sea salt, although these aren’t accurate labels because they can be misleading.
Marine salt generally refers to evaporated seawater with added minerals, while true sea salt comes from evaporated seawater without any additives.
Aquarium salts are highly concentrated and should only be used sparingly. Some brands contain more than 70 percent sodium chloride (table salt), while others include trace elements like iodine, copper, iron and sulfur compounds.
The most common use for aquarium salts is to treat ich (ick) — a parasitic disease caused by Cryptocaryon irritans — in freshwater fish tanks. This parasite lives in water and infects fish gills.
Causing them to develop white spots on their bodies. Ich usually affects fish under three inches long and can kill them if it’s not treated within 10 days of infection.
The main component of aquarium salt is sodium chloride (salt). The concentration of sodium chloride in aquarium salt can vary from 5% to 20%.
In addition to sodium chloride, aquarium salt may also contain other minerals such as potassium iodide, magnesium sulfate or calcium carbonate. The exact composition of the aquarium salt depends on the manufacturer and the intended use.
In general, it can be said that aquarium salt contains:
Sodium chloride – up to 20%
Potassium iodide – 0.5% – 5%
Magnesium sulfate – 1% – 2%
Aquarium salts are used to treat diseases in fish and invertebrates, but they are also useful in treating other conditions, such as fungal infections and external parasites.
The main ingredient of aquarium salt is sodium chloride (NaCl), which is also known as common table salt. Aquarium salt contains a variety of minerals that help replenish electrolytes lost from your fish when it sweats or sheds bodily fluids.
In addition, aquarium salt can be used to treat any condition that may cause your fish to lose electrolytes through its skin or gills.
One example would be if your fish has been exposed to high levels of chlorine in your tap water for an extended period of time and has developed fin rot due to this exposure.
If you suspect your fish may be suffering from a deficiency in electrolytes due to illness or injury.
You should consider adding some aquarium salt into the tank’s water supply immediately and discontinue use once symptoms clear up so that the fish’s body can heal itself naturally without further intervention from human sources.
Aquarium salt is also used as a treatment for certain types of parasites such as ick in freshwater tanks, but it should not be used for treating parasites in saltwater tanks as it can cause serious damage to corals and other invertebrates that live in saltwater.

Can I use table salt instead of aquarium salt?
Table salt is sodium chloride (NaCl) and has a different chemical makeup than aquarium salt. There are many other salts that can be used in an aquarium, including common table salt.
The problem with using table salt in an aquarium is that it contains iodine (I), which is toxic to fish. Some people have reported success using non-iodized table salt, but this is not recommended as the iodine content can vary from batch to batch.
Table salt also contains magnesium sulfate (MgSO4) and potassium chloride (KCl), both of which are needed by plants and other organisms in the tank. However, these minerals are present at very low concentrations and do not provide enough nutrition for plants or animals.
I can not advice you to use table salt, but it is not the same. Aquarium salt is usually made of electrolytes that are specifically formulated for fish and aquatic life, while table salt has a different chemical composition.
Aquarium salt is designed to contain sodium, potassium, chloride and magnesium ions in specific ratios. Table salt only contains sodium and chloride ions in a ratio of 2:1, which is different than the ratio needed by fish or aquatic animals.
The main difference between using aquarium salt and table salt is that aquarium salt provides the proper amount of electrolytes that your fish need to survive, while table salt does not provide these necessary nutrients.
If you use table salt instead of aquarium salt, your fish may experience health problems like swim bladder disease or other issues related to mineral deficiencies.
Additionally, if you use too much table salt in your tank, it could cause water quality issues as well as harm your fish’s gills because it doesn’t dissolve well in water like aquarium salt does.

How much aquarium salt per litre
The amount of salt you add to your tank is going to depend on the species of fish you have and the size of your aquarium. The general rule for saltwater fish is 1 tablespoon per gallon (4 liters) of water.
However, this isn’t a hard and fast rule. Some people will use less, while others may use more. It all depends on what species of fish you’re keeping and how much they need.
If you’re interested in learning more about how much salt you should be using in your aquarium, read on below!
Aquarium salt is used in a fish tank to treat certain diseases and as a preventive measure against others. It can also be used to balance the water, which is why it’s sometimes known as ‘aquarium water conditioner’.
If you have just started out with your first aquarium, then you may not know how much salt to add. When you look at all the different types of fish available.
You will notice that they come from different environments and have different needs. Some are freshwater while others are brackish water or marine.
The type of fish will determine the amount of salt required in your tank. The following table shows how much aquarium salt per litre you should add:
Freshwater fish brackish water fish marine fish
1 teaspoon (5 ml) per 10 litres 1½ teaspoons (7½ ml) per 10 litres 1 tablespoon (15 ml) per 10 litres
For most aquariums, a dose of ½ teaspoon of salt per litre will be fine. However, if the pH is low and you are adding a lot of carbonate hardness to the aquarium, you may need to increase the dose.
If you are using a liquid test kit to measure your water parameters, it is easy to work out how much salt you need by using the formula below:
Salt = [pH – 7] / 2
So if your pH is 6.0, you would use 0.3g/L or 30ppm of salt in your aquarium. If your tank has a pH of 8.0, you would use 0.6g/L or 60ppm of salt in your aquarium.

End of the line
Other than the packaging and contents being different, there is no difference between sea salt and aquarium salt. They are the same. The brands of sea salt that are sold in pet stores are exactly the same as the brands of sea salt that you will find in your supermarket.
When it comes to your fish, you want to do everything you can to keep them in top condition. So while aquarium salt may seem like a luxurious expense, you might be surprised to find out how many important benefits it brings to the table.
In the end, when used properly and regularly, this all-natural mineral supplement has the potential to be one of your most valuable tools in the fight against parasites and disease.
Aquarium salt has a very small grain size and is safe for use in reef tanks and freshwater tanks. It does not contain iodine or other additives. However, it does contain “buffering salts” to help maintain the PH of tank water.
Aquarium salt should not be used in saltwater fish only tanks. Aquarium salt is a major component of the water chemistry in a closed aquarium environment.
Using sodium chloride to season the water has several benefits including reducing the stress on developing fish, preventing bacterial infections with parasites and disease, lowering chlorine concentration in water, and increasing egg survival rates.
Read more articles: How Much Aquarium Salt Per Gallon
55 Gallon Affordable Aquarium Check It Out
Other related articles
- Which Aquarium Filter Work The Best? (Find Out ASAP)
- Are Aquarium Heaters Safe? (Let’s Find Out If Safe)
- Will Aquarium Plants Grow in Gravel? (Let’s See How)
- How Much Aquarium Salt Per Gallon for Goldfish?
- Will Aquarium Salt Kill Shrimp? (Find Out If Possible)
- Can Aquarium Plants Grow with Led Lights (Find Out)
Joseph Benson
Hi, this is Joseph Benson, aquarium is my area of expertise for years now, you can learn free aquarium tips from my page.