Television Photography: Is Crystal Reef sand REALLY Aragonite? Lets talk about that...

Everyone's favorite subject, SUBSTRATES!

Not to worry, however, as I am not starting a long open-ended dispute about the propitious effects a bare bottom tank may have over a deep sand bed, no. Today I am going to answer a question I had about a year ago.

What is this magical looking pure white sand on ebay known as "Crystal Reef"?

Does it REALLY come from the ocean?

Is it safe for gobies & sand sifters?

Is it really Aragonite?

Is it really Calcium Based?

Will it buffer pH?

Is it worth the cost?

Should I use it?

Crystal Reef branded sand has taken off in popularity in past years. It has always puzzled me, for if this truly was aragonite sand why don't we see it in local fish stores around the nation. I mean this stuff is unbelievably white! A few scratches underneath the surface reveals another unmitigated "aragonite" substrate sold to reefers.

First and foremost I must imply that I in no way have any correlation with Crystal Reef Sand Co., Natures Ocean Substrates, or sell any competitor substrate product. I just wanted to know, and in knowing, I wanted to share the knowledge.

Firstly I must say that the customer service I received from Crystal Reef was sublime. A very caring, thoughtful, and polite individual answered all my questions. Upon receiving the sand I was shocked at how bright white it actually is, after all they do make a bold claim of stocking your entire tank if you find a sand whiter than theirs.

Here is a side by side comparison of Crystal Reef [Left] and Natures Ocean Marine Grade Aragonite [Right]

*For the sake of fairness both are completely dry. Note the structure of both substrates. Crystal Reef is fairly jagged and sharp, yet the Natures ocean is smooth and individual granules are almost spherically shaped.

BUT WAIT! What is this I spy with my little eye? Can it be!

This picture was taken at a local Sand & Gravel company. This particular Dolomite is being sold at a current rate of $126/yard, roughly 2,000 pounds. ($0.06/Pound) When I seen this sand it was deceptively similar to Crystal Reef. It shimmered very similarly, it had the same angular structure,and it was just as white. (Minus some of the obvious grains of limestone and such) So I took a bag of it home to carry out a little test...

It was a little non uniform, nothing a little strainer can't fix!

Can you tell which one is which? (Apart from Natures Ocean of course.)

Shocker? :doh:

Its without a doubt that Crystal Reef is simply crushed Dolomite. That being said it is quite high quality dolomite, It has very little impurities and is a touch whiter than what I found at the local rock yard. At this time I can immediately see a downside to dolomite. It's as heavy as solid lead. Just for comparison, the aragonite in the picture (dry) weighs nearly one third that of the single mound of dolomite based sand (also dry). Another cause for concern is its angular structure. I am not sure if sand sifting critters would mind this type of sand, however I simply cannot believe that a goby would be just as happy with an angular, heavy(er), dolomite sand, than they would be with the smooth, light(er) aragonite sand. In the water the Natures Ocean aragonite felt unquestionably the softest. The Crystal Reef & Plain Dolomite felt the same, soft but *almost* too jaggedy to my sense of touch.

Now everyone's favorite, the vinegar test!

*Same lineup as before (Left-Right: Crystal Reef, Dolomite, Natures Ocean)

Crystal Reef: Very Little reaction, a few bubbles here and there, no real fizzing or serious reactions.

Dolomite: Surprisingly, the plane dolomite had more reaction than the Crystal Reef, that said I think it's because of the little tan grains of limestone mixed within the dolomite.

Natures Ocean: No surprise here, it fizzed like alka seltzer! Very noticeable reaction!

• What is this magical looking pure white sand on ebay known as "Crystal Reef"? It appears as if its just Dolomite. That being said it makes a beautiful white sand!

• Does it REALLY come from the ocean? Domolite can be found in many parts of the world, I personally doubt this particular sand came from the ocean. I could be wrong

• Is it safe for gobies & sand sifters? Difficult to tell. The company claims its safe and thats probably true, but given its angular structure I don't think its the BEST substrate if you want to keep your sand sifters very happy.

• Is it really Aragonite? Here is where I think there is a bit of false advertisement. CRYSTAL REEF IS NOT ARAGONITE! It is infact Calcite. "Calcite and Aragonite are polymorphous to each other. Although Calcite and Aragonite contain the same chemical composition, they differ in crystal structure. Calcite forms trigonal crystals, whereas Aragonite forms orthorhombic crystals." (minterals.net) It's these differentiations in the structure of the crystals themselves. The huge deal with aragonite is the orthorhombic structure is actually semi permeable (like ceramic) allowing for the growth of nitrifying bacteria within the actual grain of sand. This also explains its weight.

• Is it really Calcium Based? Yep! It has nearly the same chemical make up as aragonite, since Crystal Reef is Dolomite, so does the dolomite sand at your local Gravel Supply lot.

• Will it buffer pH? It should, but It's safe to say it will not be nearly as effective as real aragonite harvested from the ocean.

• Is it worth the cost? Eh..

• Should or CAN I use it? It depends, here is my personal list below.

Fresh Water with Goldfish, Koi, Cichlids and other fish that thrive in a higher pH.YES!

Fresh Water with Brackish Fish YES!

Fresh Water with Regular fish (tetras, betas, etc) NO

Saltwater Fish Only YES!

Saltwater FOWLER YES!

Saltwater Where Sand Sifters are Present? With Caution

Saltwater Coral Reef NO

Video Coming Soon...