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How to Choose the Correct Marine Salt for Your Marine Tank

How to Choose the Correct Marine Salt for Your Marine Tank

Comparing the Big Three Water Parameters Across Marine Saltwater Aquarium

No doubt, the three most important water parameters are calcium, alkalinity, and magnesium. And the top marine salts must have enough of these to keep a safe saltwater reef tank.

Calcium (Ca)

Calcium is essential to corals and invertebrates for building their stony skeletons. A recommended calcium level in a reef tank aquarium is 400 ppm (parts per million) in a stable water condition.

So, it would be best to go for any brand with a Ca level of around 400 ppm. Substantially lower is a wrong choice. On the other hand, significantly higher is better off. This is because if you mix your saltwater with the concentration of calcium, you may not need to supplement your aquarium for a long time.

Alkalinity (Alk)

Alkalinity can be complex to describe. However, in simple terms, it is the level of bicarbonate in your saltwater tank. Therefore, as a comparison with pure water, a saltwater aquarium has more amount of alkalinity.

If the alkalinity levels in your saltwater are somewhat too low, the corals’ skeletons will begin to dissolve. The water becomes too acidic and too poisonous for the inhabitants.

Typically, the ideal rаngе for alkalinity іn a ѕаltwаtеr аԛuаrіum is 8-11 dkh.

Keep in mind that some marine salts manufacturers may add too low or too high alkalinity levels into their product. So, measure the total alkalinity in your tank and choose a salt mix that provides the range of chemical conditions you require.

Magnesium (Mg)

Magnesium tops the list of trace elements in saltwater. However, unlike calcium and sodium, it is usually available in relatively low composition.

However, it helps balance water conditions. For example, it works with calcium in balancing the alkalinity levels in the water. So you will want to ensure that magnesium is in abundance in the salt mix brands you choose.

The ideal range for magnesium in healthy saltwater is 1250 – 1400 ppm.


How then do you choose the correct Salt Mix for Your marine tank?

The first thing here is asking yourself the type of tank you have. Are your corals and invertebrates demanding?

Although each of these reef salt mixes is similar in compositions, they have slightly varying levels of the top 3 elements.

Every tank demands varying water parameters depending on the type of corals you keep. SPS corals, for instance, are more sensitive to water changes than most LPS corals.

So, if an LPS tank does well with high alkalinity, it may hurt an SPS tank. Hard corals will benefit from adding a salt mix to the aquarium, while soft corals may not require extra benefits.

Some reefers have tanks they don’t dose at all. So, a marine salt mix with moderate water parameters is just perfect.


If you’ve got a fish-only tank or fish + soft corals tank, try Instant Ocean Reef Sea Salt Mix. If hard corals tank, use Instant Ocean Reef Crystals Reef Salt.


How to choose the correct marine salt for your marine tank

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