Guide to Buying The Best Marine Salt For Reef Tank

It is easy enough to appreciate that the hobbyist with corals in their aquarium or with a reef tank, a reliable source of saltwater is essential.

By adding the appropriate marine salt to the reef tank, it is possible to create the perfect living space for the fish and reef to flourish. It is biologically balanced and holds the right levels of foundation elements. A proper tank setup means the coral sees accelerated growth and useful for various types of corals, such as the SPS (small polyp stony) and LPS (large polyp stony) corals.

The commercial reef or marine salt helps to provide the right levels of magnesium, calcium and alkalinity.

The best marine salt for reef tank has a precision formula to replicate the natural seawater. On average, a reef tank requires a salt level of 35ppt (parts per thousand).

Luckily, there are plenty of unique and safe solutions to provide the correct salinity for the aquarium.


What is the best marine salt?

If you are getting stressed out over which marine salt is the best for your reef tank, why not take a look at our list of favorite products. Our reef salt review shortlist has the best aquarium options to create the most vibrant and appealing reef tank possible.


Red Sea Coral Pro Salt Review

red sea marine salt reviewThe Red Sea Coral Pro Salt is a perfect aquarium salt mix for that hobbyist that wishes to accelerate the healthy growth of the reef. By adding this salt mix to the aquarium, it is possible for corals to absorb the must-have trace, minor and major elements. This coral salt is a favorite for growing out the SPS coral, but still useful for other soft and hard corals. This particular salt is the preferred choice from Red Sea for growing reef, while other salt mixes are more favorable in the established or stable setups. It is packaged in a large 175-gallon bucket.



  • SPS corals easily prosper in this salt mix
  • Fast and effective at increasing the growth rate of corals
  • Quick and easy to dissolve
  • Reef and fish do well in this water



  • Slightly more expensive that alternative brands
  • Must be mixed property to avoid getting cloudy water (but this is mostly a temporary issue)


Instant Ocean Salt Review

instant ocean marine salt reviewInstant Ocean Salt (affectionately referred to as IO) is a popular brand with the hobbyists. This salt is consistent, mixes up quickly and easily and is very affordable. It is practical in reef setups and fish only systems. A major reason for its popularity with beginners is its attractive price. The pricing for the salt is highly competitive compared to most other brands in the market. This mix is packed with the must-have elements to maintain the healthy fish tank. It is easily able to give the proper salinity which is essential for the thriving aquarium and particularly useful for those with hermit crabs or similar creatures.

A 200-gallon tub comes in four individual bags to make it easier to keep from humidity and storage. It has the potential to last several months – although this depends with the frequency of water changes and tank size.



  • It is very economical
  • Salt dissolves rapidly
  • Provides must-have minerals for the right water quality
  • Easy to store
  • Versatile to use; works with both reef and fish only setups



  • Can have issues with residue build up in the mixing container


Bright Well Salt Review

brightwell marine salt reviewThe Brightwell Salt for aquarium has the ability to provide safe and effective results. It is relatively easy to mix and has solid parameters. This marine salt is useful choice if a biofuel like biopellets or similar is used. Plus, it is a great option to help the hobbyist having difficulties with pH issues and magnesium levels.

Even though it isn’t the cheapest in the market it is a worthwhile choice to invest in a salt blend for the reef tank.



  • It easily mixes
  • Replicates natural seawater



  • Salt has a quite unpleasant odor


Aquaforest Reef Salt Review

aquaforest probiotic reef salt reviewThe Aquaforest Probiotic Reef Salt is a really good aquarium product. With regular use, this synthetic marine salt easily improves on the all-round health and color of corals. It is useful for most types of coral cultures – although SPS is an area where it shines. This mix is nitrate and phosphate free. The macronutrients and micronutrients in this reef salt have the proper elements to help with the desired dyeing and growth of corals.

A single 22 kg tub of the formula has the ability to produce nearly 30-gallons of saltwater. On average, 380 g of this salt is enough to salt up to 10 liters of water.



  • Mixes fast and clean
  • No issues of residue after mixing



  • Must be used shortly after mixing to avoid issues with growing brown/golden yellow algae
  • Not the cheapest


Marine Salt Buying guide

Seawater isn’t as simple as “salty”; the water must contain a wide range of trace elements which need to be copied and feature in the artificial alternative. By investing in the high-quality aquarium salt mix it is feasible to create the type of reef tank water that is in some ways more effective than the natural seawater. The proper trace elements, pH, and calcium are necessary to promote the healthy reef invertebrates like clams and corals.


Choosing salt mixes

Not all marine salt for the reef tank is created entirely the same. For instance, there is the general tank salt that is made up of specialized mixes like cichlid or simply sodium chloride which isn’t a practical choice to bring life to a reef or marine setup. This type of salt does not include the required ions (magnesium, sulfate, chloride and sodium) that are essential for oceanic organisms to prosper.

It is more practical to invest in the purpose-made marine salt intended for the reef tank. Most of the high-quality products from brands like Red Sea Salt and Instant Ocean have slight variations in their marine salt. They typically vary in relation to the concentration of the key ions. Other signs of trace elements can also feature.

Most of the salt mixes from the different brands are easily checked in relation to magnesium, alkalinity and calcium levels. This can make it easier to choose a brand or product that matches the specific needs.

Plus, there are several types of salt mixes to match the different hobbyist aquariums or setups. For instance, there are products intended to get the coral reef, fish-only-with-live-rock (FOWLR), or fish-only tanks thriving. Make sure to use a marine salt that closely matches your intended setup.


Use a safe water supply

A major step in preparing the proper saltwater for the reef tank is to source a safe and reliable water supply. Regular tap water (municipal supply or well) is less than desirable. It has the potential to contain a variety of dissolved minerals or various chemicals that can have a negative impact on the life in the aquarium.

Pure water is favored. This is possible with the help of a specialist water filtration system. Use a high-quality system to produce safe water for the tank. There are several types of filtration systems, but the RODI units that combine deionization (DI) and reverse osmosis (RO) are typically the most favored. They have the ability to remove the most impurities or contaminants in the tap water.


Maintaining your tank

The water in the reef tank can benefit from a regular water change. On average, it helps to replace about 20 to 25% of the water every 30 days. But, still try to replace at least 10% every other week. The time-frame to change the water can be more effectively determined with the help of a water chemistry test. It is practical to mix the marine salt in advance – a day or two is useful. Once fully mixed, the bought seawater is easily stored until needed without needing to constantly stir.

Plus, a small back up amount of the prepared marine salt is useful in the event of the unforeseen accidents or emergency. Any water that evaporates is easily replaced with pure water; most salt will remain when water evaporates. Without the regular maintenance, the reef tank can soon build up with waste materials.


How much marine salt is necessary?

The amount of marine salt to buy can relate to several factors. For instance, it is necessary to determine the level of dedication, the number of tanks in the home, and the size of the tanks.

A junior hobbyist that is just starting out with a relatively small tank may be able to get away with buying a small 2 kg tub of marine salt. This helps to avoid issues with being struck with a sizable package that was quite expensive, but isn’t likely to be used.

But, for the dedicated enthusiast with a few large aquariums it will be more practical to buy the bucket at 25 kg or more, which is more cost-effective over the long-term.


Instant ocean reef crystals vs red sea coral pro

A high-quality aquarium salt mix is essential for the success of a reef tank. The most popular marine salt brands discussed by the aquarium community include Red Sea Salt and Instant Ocean.


Red Sea Coral Pro Salt

The Red Sea Coral Pro Salt product is a practical choice for the low nutrient tanks that receive regular supplements or for fish and invertebrate systems. It is created to replicate the real tropical reef water while having the slightly increased alkalinity to complement the needs of a captive environment.


Instant Ocean Reef Crystals

Instant Ocean is formulated to give utmost effectiveness for the different reef aquariums. It is rich in ocean reef elements that are higher in concentration than is likely to be noticed in actual seawater. For instance, the extra vitamins are useful to encourage the survival and vigorous growth of invertebrates in the closed marine system. Plus, the extra calcium is beneficial for the development for the small and large stony corals.



Both of these marine salts work fine in the reef tank. But the preferred choice is likely to relate to what is put in the aquarium. For instance, for the hobbyist with softies or a fish-only-with-live-rock (FOWLR), the use of Instant Ocean is certain to be ideal. However, for those wishing to keep SPS (small polyp stony), the Red Sea Salt is the more favored choice simply for the reason it has the high calcium, magnesium and alkalinity.

A further factor to consider relates to the ease and ability to mix the salt. Red Sea is quick and easy to mix and is used within a few hours, but the Instant Ocean solution is best left to mix overnight.

It may be necessary to apply a little extra calcium with the IO product – though that does depend on the method used to supplement alkalinity and calcium.

Also, Instant Ocean is favored by the hobbyist just starting out because it is quite affordable. It may be worth testing this product at first; if it doesn’t give the desired results switch to an alternative brand.



Overall, the different marine salts for the reef tanks are quite similar and most will give a satisfactory result. Our reef salt review indicated Instant Ocean is great for starting out for its affordable price, but there are still plenty of other choices available. It is essential to use the type of salt that complements the setup of the tank and what is kept inside. If the first choice doesn’t give the desired results in relation to thriving and colorful coral you may want to look at an alternative product that will increase the level of essential ions.


Leave a Reply

Your email address will not be published. Required fields are marked *