Before any aquarium can support livestock, whether fish or invertebrates, it must be completely “cycled”—another way of saying that biological filtration must be fully established in the system.
What exactly does that mean? A system is considered cycled when it has been colonized by beneficial bacteria that convert deadly ammonia - produced through the waste and respiration of fish, the decomposition of organic matter (e.g., fish food), etc. - to less harmful byproducts.
One form of bacteria converts ammonia to nitrite, which is still deadly to marine livestock. Then, another form converts the nitrite to nitrate, which is relatively harmless in lower concentrations. Partial water changes must be performed on a routine basis to prevent nitrate from accumulating to harmful levels.
How does the cycle get started?
Cycling is not simply a matter of allowing an aquarium to operate for some predetermined amount of time before adding fish or invertebrates. You can operate a new aquarium from now until the end of time and get no closer to establishing biological filtration—unless you somehow introduce ammonia.
One such method is feeding the tank—literally adding fish food on a daily basis and allowing it to decompose, thereby producing ammonia. There are also ammonium chloride solutions specifically targeted at aquarists.
Another way is by using CaribSea Arag-Alive Sand. Arag-Alive!™ makes it easy to set up an aquarium. It’s ready to work, clears quickly, and contains millions of live bacteria to cycle super fast and create a natural biological balance. Arag-Alive!™ suppresses the dreaded “new tank syndrome”, compresses the ammonia cycle, and discourages nuisance algae. In fact, independent labs prove Arag-Alive!™ cycles days faster than other brands of live sand.
The preferred way is cycling with CaribSea’s Arag-Alive sand and LifeRock. LifeRock provides everything you need to get the cycle going in one convenient package, including:
• The beneficial aerobic nitrifying bacteria
• The perfect porous substrate to allow bacterial populations to flourish
What do I do during the cycle?
It is recommended to dose daily with a quality bacteria product such as Brightwell Microbacter 7, or Seachem Stability, for the first few weeks of the cycle. You will also want to monitor the process with quality ammonia, nitrite, and nitrate test kits. As the cycle progresses, you’ll measure spiking and declining ammonia and nitrite levels followed by the appearance of nitrate.
How do I know when my tank is cycled?
When ammonia and nitrite are no longer measurable and nitrate is beginning to build up, the system is considered cycled and it’s safe to start adding livestock very slowly and incrementally. It’s important NOT to introduce a large amount of livestock to a newly cycled tank. If done, it could kick off another cycling guaranteed to kill your fish.