Best Reef Salt Mix For Your Aquarium (2024 Review)

Saltwater Aquarium with corals and marine fish species
Dr. Mollie Newton
Published by Dr. Mollie Newton PHD| Senior Editor
Last updated: July 13, 2024
Review Process and Evaluation Criteria
We conduct hands-on testing for all the products highlighted in our reviews and guides. Through anonymous product ordering and involving an independent team of testers, we gather direct experience to offer recommendations backed by data.

Do you feel dissatisfied because your reef aquarium appears empty, lacking vibrant coral and thriving marine life? Maintaining proper levels of calcium, magnesium, pH, and alkalinity might be the key. Standard marine salt may not be sufficient, but a specially formulated reef salt mix could transform your aquarium into a lively and healthy masterpiece. Initially, I used regular marine salt, and my corals and marine life did not thrive. However, after switching to a specially designed reef tank salt mix, I observed a remarkable improvement in my tank. Continue reading to learn about the best reef salt mixes available.

Article Summary

  • The reef salt mix is a precise blend of salts designed to mimic natural seawater, providing a balanced ratio of magnesium, calcium, alkalinity, and pH essential for reef tanks.
  • The use of reef salt helps maintain stable pH levels and provides a controlled environment that supports the health of marine life in the aquarium.
  • Reef salt mixes are specifically formulated to support the growth of stony and soft corals in reef aquariums.

On to the Reviews…

Top Pick

Red Sea Fish Pharm Coral Reef Marine Salt

Red Sea Salt reef crystals are an excellent choice for aquarists who need a high-quality salt mix for large marine tanks as there is enough salt to last for 175 gallons of water. It contains all the minor, major, and trace elements like calcium, magnesium, and bicarbonate your fish and corals need to thrive.

Top Pick: Red Sea Fish Pharm Coral Reef Marine Salt

The best reef salt mix for medium to large reef aquariums is the Red Sea Salt Fish Pharm Coral Reef Marine Salt as you get enough product for 175 gallons of water. It’s based on the natural salt harvested by solar evaporation, making it almost as good as natural sea water for your fish!

It’s enriched with other fine minerals to allow for healthy saltwater fish like clownfish and royal grammas, invertebrates, and coral growth. This sea salt mix is particularly beneficial for low-nutrients setups that are regularly dosed with individual elements.

The only minor downside of these reef crystals is that the salt bucket it comes in is a little flimsy as it can sometimes arrive damaged.


  • Dimensions: 7.84” x 3.94” x 3.94”
  • Weight: Not Specified
  • Liquid Volume: 175 Gallons


  • Based on natural sea salt
  • Enriched with fine minerals
  • Great for large large reef tanks


  • Salt bucket is a little flimsy
Best Value

Brightwell Aquatics NeoMarine – Marine Salt Blend for Reef Aquarium

This salt mix from Brightwell Aquatics Neomarine is the best reef salt mix for reef aquarists on a budget. It contains a precise blend of major and minor elements to allow for healthy fish and coral growth.

Best Value: Brightwell Aquatics NeoMarine – Marine Salt Blend for Reef Aquarium

If you’re looking for the best reef crystals for reef tank owners on a budget, you can’t go wrong with the Marine Salt Blend from Brightwell Aquatics. Onced mixed with water, it will accommodate reef aquariums up to 50 gallons in volume.

It simulates natural seawater as it’s made up of a precise ratio of minor, major, and trace elements. It’s completely safe for marine animals and contains USP, ACS reagent-grade, and FCC food-grade ingredients.

This sea salt mix is manufactured in the USA under very strict quality guidelines – for instance, the elements in the mix are provided by individual salts rather than seawater evaporite.

This ensures consistency with each batch and prevents any dips in quality. It contains zero ammonia, nitrate, phosphate, and organic substances, too, at standard specific gravity – your fish only deserve the best, after all!

The main downside of Brightwell Aquatics salt mixes is that they can leave a lot of sediment on the bottom of your aquarium once mixed, causing your aquarium to look cloudy. However, this is only temporary and should clear up within a day or so!


  • Dimensions: 12.75” x 3.5” x 17”
  • Weight: Not Specified
  • Liquid Volume: 50 Gallons


  • Replicates natural seawater
  • Contains the accurate ratio of major, minor, and trace elements
  • Manufactured under strict quality guidelines


  • Can make your saltwater aquarium look cloudy temporarily
Editor’s Choice

Tropic Marin Pro Reef-Bucket for Aquarium

Tropic Marin Pro Reef-Bucket for Aquarium is the best salt mix if you have corals, particularly SPS (Small Polyp Stony) corals, in your reef aquarium. It contains the right concentrations of calcium and magnesium for modern reef aquaria (regular dosing, of course!).

Editor’s Choice: Tropic Marin Pro Reef-Bucket for Aquarium

If you can afford to spend a bit extra on saltwater salt mixes, the Tropic Marin Pro Reef-Bucket for Aquarium is the best reef salt mix for you. I personally use this aquarium salt mix in my saltwater aquarium and it has never let me down!

You get enough saltwater aquarium salt for 200 gallons of water once it has been mixed, making it one of the best salt mixes for large marine aquariums with big fish like emperor angelfish and groupers. It’s made from pharmaceutical-grade sea salt that is designed especially for a marine environment.

It contains the right blend of magnesium and calcium levels to ensure proper coral growth, including sensitive SPS coral species.

However, these reef crystals can occasionally turn your reef tank water brown. This doesn’t harm your aquatic life, but it can make your marine aquarium look a little unsightly.


  • Dimensions: 38” x 38” x 38”
  • Weight: 55 lbs
  • Liquid Volume: 200 Gallons


  • Pomotes coral growth
  • Correct balance of calcium and magnesium
  • Ideal for sensitive corals species


  • Can occasionally turn your water brown

Red Sea Fish Pharm Coral Pro Marine Salt for Aquarium

Red Sea Fish Pharm ARE11230 Coral Pro Marine Salt for Aquarium is a solid choice for saltwater aquarists who own SPS, LPS, and soft corals. It contains the foundation elements to encourage healthy and strong corals.

Red Sea Fish Pharm Coral Pro Marine Salt for Aquarium

The next best salt mix is Red Sea Coral Pro Salt, which is targeted for marine aquariums containing soft, SPS (Small Polyp Stony), or LPS corals (Large Polyp Stony like frogspawn. Compared to some other salt mixes, Red Sea Coral Pro Salt provides the basis for quick and healthy growth of corals.

It contains an exact blend of calcium and magnesium, alongside carbonates to ensure your corals take in the right amount of nutrients to thrive and grow.

The salt mix is harvested naturally from the Red Sea and contains no toxic levels of heavy metals or chemical binders. It has a low moisture content and doesn’t contain any nitrates or phosphates (both of these can contribute to algae like coralline algae, which is a type of red algae), which is a mark of quality.

Similarly to the salt mix by Red Sea Fish Pharm I reviewed earlier, this other salt mix from the same company comes in a flimsy plastic bucket that is easily damaged.


  • Dimensions: 3.54” x 3.54” x 3.54”
  • Weight: Not Specified
  • Liquid Volume: 175 Gallons


  • Harvested naturally from the Red Sea
  • Contains the correct balance of magnesium, calcium, and carbonates for corals
  • No phosphates or nitrates
  • Doesn’t contain toxic levels of heavy metals


  • Red Sea blue bucket is a little flimsy

Seachem Vibrant Sea – Highly Concentrated Synthetic Sea Salt

Seachem Vibrant Sea Synthetic Sea Salt is a highly concentrated salt mix that contains all the essential major, minor, and trace components required for a mixed reef tank. It boasts proper strontium, calcium, and magnesium levels that enable the growth of soft and stony coral species.

Seachem Vibrant Sea – Highly Concentrated Synthetic Sea Salt

Next up is this marine aquarium salt mix from Seachem, which is a highly concentrated blend of synthetic salts designed especially for saltwater aquariums. It’s made up of all the essential trace, minor, and major elements that occur naturally in sea waters, alongside potassium.

It’s a great option for reef setups as it contains the correct strontium, calcium, and magnesium levels with accurate pH and alkalinity, all of which is essential for healthy SPS and LPS corals.

The salt mix is free of both nitrates and phosphates, which is an excellent feature as mixing saltwater with it won’t contribute to algae. I also really like that this salt mix is fast dissolving as you don’t have to wait ages for it to start working, unlike some other salts.

My main gripe with this marine salt from Seachem is that it has a tendency to leave behind a coating once it has been mixed.


  • Dimensions: Not Specified
  • Weight: 50.71 lbs
  • Liquid Volume: 220 Gallons


  • Highly concentrated formula
  • Contains all necessary trace, minor, and major elements
  • Enhanced levels of calcium, strontium, and magnesium
  • Nitrate- and phosphate-free


  • Can leave behind a coating once mixed

Fritz Aquatics FZ Pro High Alk Salt Mix

Fritz Aquatics Reef Pro Mix is a solid option for aquarists that need a reliable and good-quality salt mix for their tank.

Fritz Aquatics FZ Pro High Alk Salt Mix

One of the most popular salt mixes to use for a saltwater tank is the Fritz Aquatics FZ Pro R.P.M High Alk Salt Mix, which provides all the necessary minor, major, and trace elements you need for a stable marine habitat.

Reef Pro Mix also features enhanced alkalinity levels and is completely free of phosphates, nitrates, and ammonia too! It’s particularly advantageous to SPS corals due to its high alkalinity.

However, Fritz Aquatics seawater mixes don’t produce as much saltwater as some different salt mixes, so they may not be the best choice for large setups.


  • Dimensions: 10.5” x 15” x 11”
  • Weight: 55 lbs
  • Liquid Volume: 200 Gallons


  • Contains all the essential major, minor, and trace elements you need
  • Ideal for SPS corals
  • Free of nitrate, phosphate, and ammonia


  • Doesn’t produce a lot of saltwater once mixed

Continuum Aquatics Halcyon – Marine Reef Salt

These reef crystals from Continuum Aquatics Halcyon have been precisely formulated and blended to replicate the salt from natural oceans.

Continuum Aquatics Halcyon – Marine Reef Salt

One of the last best reef salts I recommend for a reef tank is the Continuum Aquatics Halcyon Marine reef crystals as they have been carefully formulated and balanced to mimic natural ocean water.

The reef crystals are made from reagent-grade and pharmaceutical-grade ingredients that have been tested and developed by experts in manufacturing salt mixes. Better yet, it’s produced in small batches under strict quality controls to ensure its safety and high standard.

The main downside of this professional marine salt mix is its price. It’s quite costly for the amount of salt you get (only around 50 gallons of saltwater once mixed), so you’d need to purchase multiple bags if you have a large reef tank.


  • Dimensions: 3.5” x 12.5” x 17”
  • Weight: 14.92 lbs
  • Liquid Volume: 50 Gallons


  • Mimics natural sea waters
  • Made from reagent-grade and pharmaceutical-grade ingredients
  • Manufactured in small batches to maintain a consistent quality


  • Quite costly

What Is Reef Salt Mix?

Reef salt mix is a precise blend of salts that mimic natural sea waters. It contains a balanced ratio of magnesium and calcium (sometimes strontium, too!), along with ideal alkalinity and pH levels that are essential for reef tanks.

Reef Salt Mix Components

Unlike regular marine salt, reef salt mixes are higher in both calcium and magnesium with accurate levels of alkalinity and pH to encourage the growth of corals. The main 3 components a high-quality salt mix should have are: alkalinity, calcium, and magnesium.

The best salt mixes will have high levels of all of these components, so this is a good way to check whether the salt mix you’re using is of a high standard.


Alkalinity is essentially the amount of bicarbonate in your reef water. This is an important part of a salt mix as seawater has a pH of around 7, unlike pure water.

Saltwater tanks need alkalinity in the form of bicarbonate as, otherwise, the water will be too acidic and will poison your fish and dissolve your corals’ skeletons. The ideal range for alkalinity is 8-11 dKH (degrees of carbonate hardness).


The majority of salt mix manufacturers refer to the concentration of bicarbonate as alkalinity, so don’t worry if you don’t see bicarbonate in the ingredients list!


Calcium is essential in a reef salt mix as both invertebrates and corals need it to build strong skeletons. Ideally, your reef aquarium should have 400 ppm (parts per million) of calcium to keep your invertebrates and corals healthy.


Magnesium is a trace element that is found in seawater. As a trace element, it makes up a low percentage of the other elements in seawater like chloride, sodium, and calcium.

That said, magnesium is a crucial component of your reef setup as it helps balance out alkalinity by interacting with bicarbonate to stop it from triggering calcium carbonate, the latter of which would get rid of the vast majority of the salt and alkalinity in your aquarium.

The ideal range for magnesium in a reef aquarium is between 1250 and 1400 ppm.

Mined vs Synthetic Salt Mix

Mined and synthetic salt mixes are the same – they both contain mined ingredients, which are then mixed in a laboratory. However, natural/evaporative salt mixes and mined/synthetic salt mixes are quite different from one another, which I’ll go over below.

Natural/Evaporative vs Synthetic Salt

Natural/mined salt mixes are harvested from natural sea waters that have gone through a process called desalination to remove all the pure water. Synthetic salts contain mined ingredients that are then formulated and mixed in a laboratory.

Both types of salt mixes should be readily available online or at your local fish store!

Why Use a Reef Salt Mix?

saltwater reef aquarim under blue light
A Saltwater Reef Aquarium With Corals And Colorful Fishes

The best reason to use reef salts is because they are safer and more convenient to use than actual salt water. Marine salt mixes contain buffers to keep your pH, alongside magnesium, calcium, and other trace elements that are essential to invertebrates and corals.

What Type of Reef Salt Do You Need?

Any reef crystal mix will do the trick for a reef environment, but there are a few products I personally recommend for specific setups.

SPS Tanks

If you have an SPS tank, I’d recommend using Red Sea Coral Pro or Tropic Marin reef crystals as both these two salt mixes contain good levels of magnesium and calcium. Fritz Aquatics FZ Pro High Alk Salt Mix is also a solid choice!

LPS Tanks

Red Sea Salt Coral Pro and Brightwell Aquatics reef crystals are both great options for LPS tanks. The former is naturally harvested from sea waters, whereas the latter has been formulated to mimic natural salt waters!

Mixed Reefs

For mixed reef aquariums, I think Seachem Vibrant Sea is an excellent option as it’s free of nitrates and phosphates while also providing ideal levels of magnesium, calcium, and strontium.

What Is the Difference Between Reef Salt and Marine Salt?

The main difference between reef crystals and ordinary marine salt is that reef salt mixes contain higher levels of calcium and magnesium, both of which are crucial to the growth of stony and soft corals.

What Is the Best Reef Salt Mix?

The best reef crystals contain high levels of magnesium, alkalinity, and calcium, in addition to buffers to help you maintain a stable pH and alkalinity.

What Type of Fish Tank Is Best for a Saltwater Reef?

This mostly depends on personal preference and how big you want your reef setup to be. I personally use an acrylic tank (the Coralife Biocube if you were wondering!) for my mixed reef as acrylic tanks are more durable and lightweight than glass aquariums. However, there are other excellent options available for reef tanks as well.

This makes them useful for large reef setups that contain a lot of water – you’ll also be able to lift up your tank a lot easier if you need to relocate it.

However, acrylic aquariums are easily scratched (my aquarium is covered in quite a few!) and they are usually more expensive than glass tanks, so these are things to keep in mind.

What Brand of Reef Salt Is the Best?

There are many great reef salt mixes on the market, so it’s difficult to narrow down the best brand. However, some of the most popular reef salt brands include Red Sea, Tropic Marin, and Seachem.

I personally use Red Sea in my reef tank, but I’ve used the aforementioned brands before and they’re equally as good!

Can You Use Too Much Aquarium Salt? 

Yes, you can use too much marine aquarium salt. But adding too much salt to your reef tank can be detrimental to the health of your fish, invertebrates, and corals.

  • Based on sea salt naturally evaporated by the sun
  • Enriched with fine minerals
  • Ideal for large reef tanks

  • Simulates natural sea water

  • Contains a precise ratio of major and minor elements
  • Crafted under strict quality guidelines

Best Value

  • Ideal for coral growth
  • Good ratio of magnesium and calcium
  • Can be used for sensitive corals

Editor’s Choice

Final Thoughts

I hope this guide on the best reef salt mixes helped you choose the right one for your reef tank. Which reef crystals are your favorites? I’d love to hear your thoughts over on our social media platforms.

Be sure to share this post with other saltwater aquarists so they can learn about reef salt mixes, too!

You May Also Like