What's in Your Aquarium? Don't get caught buying fake oolitic aragonite!

Keeping an aquarium is a fun hobby, whether you have a small goldfish tank or an elaborate marine tank. It can be as simple or as difficult as you make it. When you’re setting up your aquarium, one of your first and most important purchases is the substrate. Substrate is the layer of sand or gravel that you place at the bottom of your tank. Choosing the right substrate directly impacts the health of your tank. For example, in a freshwater tank, you would want to use a gravel or rock that won’t affect the pH of the tank. However, in a marine tank, there are options that will help you maintain a stable pH, without the addition of chemicals. The best substrate for this is oolitic aragonite. Coral sand can also be used, but it’s buffering capabilities aren’t as effective and it is usually unsustainably collected, and its collection can damage the reefs. 

Oolitic aragonite is a unique type of biogenic calcium carbonate. It naturally forms on the banks of The Bahamas on a sustainable and renewable basis. Due to its renewable nature, it is an environmentally responsible alternative. It has no harmful tar, impurities, or organics and is the ideal substrate for marine, reef, and cichlid aquariums. Oolitic aragonite has unsurpassed buffering capabilities and helps to maintain a natural pH balance of 8.2 without the constant addition of chemicals. One kg of aragonite also offers over 1 million sq. cm. of surface area providing a huge space for housing ammonia, nitrate, and nitrite reducing bacteria. It’s also the ideal grain size for reef tanks, fish tanks, plenum systems, and refugiums. Another benefit is its lack of silica, which helps to prevent diatom blooms in your tank. You’ll be hard pressed to find a better substrate for your marine, reef or cichlid tank. 

Unfortunately, however, there are many substrates out there that are all a bit of smoke and mirrors. They masquerade as oolitic aragonite, but under close inspection, they are either coral sand or just regular calcite sand. In order to reap all of oolitic aragonite’s benefits, you need real oolitic aragonite. Otherwise, you’re paying a premium for a substandard product that won’t perform the same as real oolitic aragonite. Fortunately, it’s quite easy to tell if what you are purchasing is indeed real oolitic aragonite. 

The easiest and quickest way to figure out if the product is indeed real aragonite is to look at the individual grains closely. Grains of oolitic aragonite are smooth and spherical. The word “oolitic” literally means egg-shaped. If the grains you are observing are rough and angular, this is likely just crushed shell or regular sand. It’s important to note that some aragonite substrates are a mix of oolitic aragonite and crushed shell. If you see a combination of spheres and angular crushed shell, this is likely a mix. It will provide the same benefits as purely oolitic aragonite since it still contains oolitic aragonite. The difference between them is simply aesthetic. 

Figure 1. Quick and easy way to determine if you have oolitic aragonite.

Once we found out that there were some substrates masquerading as oolitic aragonite, we decided to take our analyses further. We went to the local pet store and bought a substrate that was labeled to contain “Bahamas Oolite Aragonite” to compare it to our oolitic aragonite that is sustainably harvested from The Bahamas. We had some remarkable findings!

Take a look at the below image of our oolitic aragonite compared to the other store-bought product labeled as oolitic aragonite. Do you see the round spheres in the image on the left? Those are oolitic aragonite grains – called “ooids.” Notice how the product on the right doesn’t have any round spheres and the grains are angular – that is simply regular sand and will provide none of the benefits discussed above. Unfortunately, the sand on the right is being sold as oolitic aragonite!

Figure 2. Comparison of Calcean’s Oolitic Aragonite to a common store-bought brand labeled as “Bahamas Oolite.” Calcean (Left). Store-Bought Brand (Right).

After our initial visual inspection showed that there were no ooids, we examined the material under our lab’s microscope. You’ll notice the difference between our oolitic aragonite and the other store-bought product. Calcean’s oolitic aragonite has distinct spherical grains (ooids) whereas the other store-bought brand has angular grains indicating that it is not oolitic aragonite.

Figure 3. Comparison of Calcean’s Oolitic Aragonite to a common store-bought brand labeled as “Bahamas Oolite.” Calcean (LEFT). Store-Bought Brand (RIGHT). Note the spherical grains on the LEFT compared to the angular grains on the RIGHT.

We then took it a step further, conducting what is called the Feigl’s Solution test. This is a classic test used to determine whether a material is aragonite or calcite. When aragonite is exposed to the Feigl’s chemical solution, it will react and turn black immediately. It’s a quick and easy way to tell if what you have is aragonite. As you can see below, the store-bought “Bahamas Oolite Aragonite” is still white and our material turned black immediately. 

Figure 4. Results of the Feigl’s Solution Test. This test determines aragonite from calcite. Aragonite immediately turns black when exposed to the solution. Calcite remains white. Note that calcean’s OoLITIC ARAGONITE TURNED BLACK IMMEDIATELY INDICATING IT IS INDEED ARAGONITE WHEREAS THE STORE-BOUGHT BRAND REMAINED WHITE INDICATING IT IS NOT ARAGONITE.

Another issue to look for is material that is sold wet. The packaging will make claims of live bacteria, but there are no more bacteria on wet material than there are on dry material. This means you’re spending money on water rather than actual substrate. We actually dried and measured the amount of water in a 20lb and 10lb bag of store-bought wet or “alive” substrate. There was 4lbs of water in the 20lb bag and 2lbs of water in the 10lb bag! When you buy dry material, you’re getting what you pay for: substrate. There’s no need to pay for water!

 We were dismayed to see that companies are fooling the public into buying a falsely-labeled material, foolitic fauxragonite if you will. At Calcean, we strive to provide the best and most consistent quality products. Oolitic aragonite has a number of benefits and is an excellent aquarium substrate, when what you have actually is oolitic aragonite! You don’t want to waste your money on fake aragonite and water. Be a diligent consumer and examine your substrates closely and confirm the source. We’re proud to say that we provide sustainably harvested REAL oolitic aragonite. 

Calcean & Pisces usa’S REAL OOLITIC ARAGONITE PRODUCTS. soLD ON AMAZON & CHEWY.

What is Oolitic Aragonite?

Oolitic Aragonite: Nature’s Renewable Sand from the Ocean

            Beneath the gin clear waters of The Bahamian banks lies a unique mineral that looks much like sand but is unlike the sands on the beaches of Florida or California. This unique mineral is called Oolitic Aragonite. It is a distinct type of Calcium Carbonate and while it has the same chemical make-up, it looks different under a microscope providing it some irreplaceable advantages. Most calcium carbonates look like building blocks under a microscope, however, oolitic aragonite looks like lots of interlaced needles. This affords aragonite many advantages, such as a higher surface area. The average person interacts with calcium carbonate daily as it is extremely versatile and as such, is used in many different applications.  It is found in your toothpaste, your antacids, as a filler in many of your plastic products, your morning orange juice, your morning newspaper, the carpet under your feet, and even in the car that you drive to work.   However, the calcium carbonate used in these applications is sourced from non-renewable resources: mines all over the USA, ranging from Florida to Idaho. This type of calcium carbonate mining is energy intensive, has a large carbon footprint, and is not sustainable. However, there is an alternative that is environmentally responsible: oolitic aragonite. Oolitic aragonite naturally pulls carbon dioxide from the atmosphere during its formation and is a renewable resource. 

            Oolitic aragonite is biogenic meaning that it is produced by living organisms. It naturally forms during events called ‘whitings.’ Whitings can be seen in satellite imagery as wispy white clouds in the water. At first, researchers believed these to be caused by schooling fish disturbing the sandy bottom. However, it was found to be an event where oolitic aragonite forms. Blooms of phytoplankton (microscopic plant organisms) seasonally move over the shallow banks of The Bahamas. As the phytoplankton convert the sun’s rays into energy, carbon dioxide is pulled from the atmosphere. The carbon dioxide then binds to the calcium in the water, creating a calcium carbonate known as oolitic aragonite. The white clouds in the water are actually oolitic aragonite forming. Oolitic aragonite is one of the world’s only biogenic and naturally precipitated calcium carbonates and happens extensively in The Bahamas. These whitings events happen bi-annually, constantly replenishing the oolitic aragonite deposits. The oolitic aragonite reserves on The Bahamas banks are estimated to contain 50 to 100 billion metric tons. The estimated annual renewal rate is 14 to 120 million metric tons per year. Carbon dating, a common method for determining the age of something, showed that much of the material is new, having been created in the past 3 to 5 years. Oolitic aragonite is truly a renewable resource. 

            Now, more than ever, is the time to focus on environmentally responsible alternatives. Oolitic aragonite is biogenic, renewable, and sustainable. Ethically and sustainably harvested, oolitic aragonite provides an environmentally responsible alternative to other calcium carbonates. There are some key markets that oolitic aragonite is a great contender in ranging from aquarium sand to agriculture. Consumers and companies alike should be aware of their options so that they can make the responsible decision. 

Aquarium

            Oolitic aragonite is a perfect substrate for marine and cichlid aquariums because it naturally buffers the pH. Unfortunately, many brands in the aquarium market claim to be aragonite but are actually just crushed limestone from the land-based mines. There are also some brands that do not have the correct approvals to harvest aragonite, meaning your tank may have illegally harvested substrate in it. Always double check your aragonite and its source. Ask companies where they source their aragonite. You’re missing out on the many benefits of aragonite by purchasing limestone that is falsely labeled, shorting yourself and shorting the environment. 

Play Sand

            Oolitic aragonite is also a great eco-friendly option for play sand. Many play sand brands currently on the market are sourced from silica based sands. Silica exposure has been linked to silicosis, a dangerous respiratory disease. Play sand should be safe for children to play in and unfortunately, most standard sands on the market are unsafe. Oolitic aragonite is silica free, quartz free, and dust free. It is also smooth and round in structure, whereas other sands are rough in texture. It’s perfect for building sandcastles and can safely be used both indoors and outdoors. When sourcing play sand for your children, it is important to consider not only their safety, but also the texture and quality of the sand. Oolitic aragonite is the perfect alternative to standard sands. If used outdoors, it can also help your garden. 

Agriculture

            Agriculture is another area where oolitic aragonite shines as a superior environmentally friendly alternative. It is a great soil enhancement and chicken feed additive. Oolitic aragonite contains approximately 40% elemental calcium and beneficial amino acids, providing much needed calcium in an efficient bio-deliverable means to both plants and egg-laying hens. It also holds nutrients in the soil where they belong, preventing leaching into the environment. It’s also easy to add to your garden or spread on your crops. 

Plastics

            In ground and coated form, oolitic aragonite can be used as fillers for plastics. This represents another great opportunity to help the environment through reduction of carbon footprint by reducing the amount of hydrocarbon based plastics consumed.  In compostable bioplastic products the oolitic aragonite, with its high PH buffer, may act as a neutralizing agent to acidic polymers such as PLA and its base form of lactic acid when material degrades.  Its unique crystalline shape will enhance physical properties such as stiffness, impact, and heat distortion temperatures. Studies are also being done as to the effectiveness as a nucleating agent when compared to talc as its unique shape offers plenty of nucleating sites as compared to the spherical shape of mined calcium carbonate.  In plastics applications use of this mineral may not only reduce your compound or plastics costs, but you may also get many additional added benefits such as those just described, all while contributing to your sustainability initiatives.

            These are just a handful of the applications in which oolitic aragonite can be used as an environmentally responsible alternative. This blog will be the place to read more about all the different applications oolitic aragonite can be used in. The next time you are out shopping for your fish tank, your children, or your garden, ask questions and make sure you are purchasing real oolitic aragonite from a reputable source.