The 5 Best Live Sands for Reef Tanks

Best Overall

Nature's Ocean Bio-Activ Live Aragonite

$33 at Amazon $28 at Chewy View on Petco

This product is sustainably harvested from the ocean and packaged in as close to a natural state as possible. It contains beneficial bacterial colonies, in addition to aragonite, a naturally occurring form of calcium carbonate; this calcium carbonate acts as a buffer against changes in your tank's water, promoting a healthy and consistent pH. Meanwhile, the bacterial colonies work to decrease your ammonia and nitrite levels.

It looks great too, with tiny shells added to the mix for a more varied appearance. The sand also settles quickly, with any cloudiness usually dissipating within a few hours.

Nature's Ocean has so much faith in its patented method of harvesting live sand that it guarantees that each pound of its sand contains more than 10 million live bacteria. This rich ecosystem starts working immediately to filter your tank's water and move it toward a fish-safe equilibrium. It also provides essential inorganic elements, including cobalt, zinc, and molybdenum, in addition to a variety of trace elements.

Nature's Ocean Bio-Activ Live Aragonite Reef Aquarium Sand comes in several different colors and gradients to best match your saltwater tank. For example, Natural White #1 has grains between 0.5 and 1.7 millimeters, making it an excellent, uniform choice for most saltwater tanks, including those with bottom-dwelling fish. The Natural White #0 version has a finer grain—between 0.1 and 0.5 millimeters—which is more likely to get kicked up by direct filter and powerhead outflows, but can be a good choice for aquariums with algae eaters that like to pick through sand, such as hermit crabs or snails.

_{Sizes: 10, 20, and 40 pounds | Varieties: Black beach, white sand #1, white sand #0, reef substrates, Samoa pink, Australian gold}

Best Pink

CaribSea Arag Alive 20-Pound Fiji Pink Sand

$33

$30 at Amazon View on Chewy $33 at Petco

Many saltwater aquarists enjoy the contrast that pink sand provides compared to plain white or natural sand. CaribSea Arag-Alive Fiji Pink Sand is a medium grain at 0.5 to 1.5 millimeters, so it is not kicked up easily by filtration, and bottom dwellers have an easy time moving it around.

The sand’s microorganisms are engineered to reduce “new tank” syndrome, where ammonia and nitrite levels become dangerously high—a common symptom in environments that haven’t had time to develop the proper levels of bacteria. It also discourages problematic algae growth and helps to maintain the correct pH balance. 

Like most pink sand available on the market, it will have a mix of pigments—including brown, pink, and white grains—giving this sand a spectacular appearance in a natural reef environment.

_{Sizes: 10, 16, and 20 pounds | Varieties: Special grade reef, Bahamas oolite, Hawaiian black, Bimini pink, natural reef}

Best Black

CaribSea Arag Alive Hawaiian Reef

$43 at Amazon View on Petco

For bold contrast, some marine aquarists go with a black substrate. Black sand is great at setting off the color of vibrant corals and marine fish. A darker substrate is recommended, specifically when dealing with lower-light species, such as flashlight fishes. It is a starkly different aesthetic from most marine tanks.

The Hawaiian Black Sand from CaribSea also has a larger grain size—between 0.25 and 3.5 millimeters. Combined with its black color, this makes the Hawaiian Black option a little more low-maintenance. Grains are large enough that they won't swirl around or get sucked into intakes, while the black color won't show algae spotting like white sand does.

_{Sizes: 10, 16, 20 pounds | Varieties: Special grade reef, Bahamas oolite, Fiji pink, Bimini pink, natural reef}

Best Fine

Nature's Ocean No.0 Bio-Activ Live Aragonite Live Sand

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Fine sand gives an exceptional texture to any reef environment and is great for bottom-dwelling fish and invertebrates to enjoy. Nature’s Ocean White Reef Sand features grains between 0.1 and 0.5 millimeters.

While fine, white sand can give a clean look to a reef tank, it requires a little more maintenance. Carefully direct filter and powerhead outflows in order to limit substrate drifting. Powerful currents can easily lift fine substrate, and it will not settle out, causing a cloudy tank appearance.

The hardest part about dealing with white substrate is that it will look dirty more frequently than other colors. White grains will quickly pick up algae that will be more noticeable than with tan, pink, or black substrates. It is better for tanks with a lower bioload or those that are meticulously cleaned by their owners or the tank’s inhabitants.

_{Sizes: 10, 20, and 40 pounds | Varieties: Black beach, white sand #1, reef substrates, Samoa pink, Australian gold}

Best Coarse

CaribSea Arag Alive Natural Reef Gravel

$33 at Petco

With grain sizes from 0.2 to 10.0 millimeters, CaribSea Natural Reef Gravel is a great natural element to add to any reef tank. The larger grain sizes aren't likely to be moved around easily by filtration elements, and most bottom-dwelling fish and invertebrates do not have trouble relocating them. There is no rinsing required; it cycles out the water fairly quickly and never needs replacement.

This sand is not recommended for fish that require full sand burrows, but it can be mixed with smaller-grain sand to provide some weight and contrast to the marine environment. Additionally, the gravel provides greater surface areas for bacteria to assist with a faster cycle and discourage nuisance algae growth.

_{Sizes: 16 pounds | Varieties: Special-grade reef sand, Bahamas oolite, Fiji pink, Bimini pink}