Modern ReefKeeping

What is Live Sand?

Lets first look at what makes Live Sand (LS) exactly that, live. The vital aspects of a quality live sand are the microscopic bacteria, tiny crustaceans and macro organisms that offer biological filtration by breaking down and consuming organic matter. Live sand ( LS ) is often collected straight off the reef.  It can also be cultured by taking dry dead sand and mixing it with some live sand until it becomes live by increasing populations of the bacteria and organisms.
In the typical set up of a new aquarium, it has often been suggested to use a pound or more of live sand per gallon of water with exceptions to preference or the desire of a Deep Sand Bed (DSB). A quality LS will have roughly 10 Million live organisms per pound. Lets do a little math on this one. *With 65 gallons of water you would use roughly 65 pounds of sand. With 10,000,000 or so organisms per pound, you now have 650,000,000 organisms. That’s an outstanding number of things meant to help clean and filter your tank.  Unfortunately, for the next few weeks you won’t even have anything giving them a food source,  i.e  fish,coral or invert waste and bi-products.
The Life and Death of Live Sand
No species of life can be sustained without a food source. As the organisms in your live sand begin to die off it causes two different sort of “cycles” that you must be aware of. The die off causes a rise in ammonia and nitrate that are part of a typical cycle. It also provides a food source for the remaining organisms, which in turn reproduce thus adding to the numbers. This cycle of,  die off…. food source…. die off , will continue until it levels itself out with the dying organisms feeding the living organisms. For the majority of reefers, this cycle is excruciatingly slow. Though its in the best interest of your future tank inhabitants to let it run its course. This usually takes between 4-8 weeks, give or take the cycle of your Live Rock (LR). (Cycling LR is much like cycling LS, many many organisms in the LR can die off from shipping)

When I set up my reef tank, I chose an alternative method. I already had established LR from another tank and was not concerned there would be any sort of die-off on the LR. My only concern was the cycling of LS. I chose to go with dry dead sand, which is sand that had come off a reef, but let out to dry. This sand is  then cleaned of organic matter which can break down and cause spikes once in the tank. With this organic matter free sand I was able to set my tank up with such a small cycle that the only indication of a cycle  being  a slight outbreak of diatoms and cyano bacteria. The basic tests of ammonia and nitrates were run every day for 4 weeks with no raise above normal levels required to keep a successful reef. I had added my fish and corals within 3 days with no sign of distress.

Another alternative to using ALL LS is to add a small percentage of LS to your dry sand. In turn making it a full live substrate in a short amount of time. Thus greatly dropping the number of possible organisms to die off causing a spike. This is something I would recommend over either of the two ways listed above. Its not harsh on the cycling itself, but you get the added benefits of having live sand as a seed to the rest of your sand.

The Keys to Remember
With all this written about cycles and the shortening of them , I would like to mention that it is imperative to your future success that you research all avenues of marine aquaria. Quality biological filtration is second to none when it comes to the success of your aquarium. Knowing where and how you came to acquire your LR will go a long way into helping make the LS decision. If your LR isn’t fully cured when you receive it, then there wouldn’t really be any reason NOT to use ALL LS because your aquarium will have a heavy cycle regardless. Also keep in mind that when your aquarium is technically ready for livestock you may very well still need to add things slowly. In my case I had a few small fish, and some small frags of coral which the bacteria and small organisms needed to help clean the organic matter had time to “catch up” to the new bio-loads.

When we discuss LS coming straight off the reef and thinking more is better with those micro organisms we need to remember just how diverse a wild reef is compared to our aquariums which are far less dependant on these organisms than in the wild.

So in review, doing the research in the beginning of your marine aquaria adventure will greatly add to the years of enjoyment that are to follow. With all the things about keeping reefs we DO know, there is so much we are continually learning.

*Throughout this article I will be using my personal tank as an example. The tank is a 65 gallon tank with a footprint of 48″x18″.

Written by Justin Hoss (hosser)

Edited by Adam J