Starting the Cycle in Your Tank
In the first part of The Nitrogen Cycle blog, we went over the process of the nitrogen cycle within your aquarium. So what do you do with that information? If you are struggling with ammonia and nitrite problems, it's likely a cycling issue. Use one of these methods when you start a new aquarium or at any time to establish a good bacteria base.
Starting the Cycle with Fish
The
bacteria required for the nitrogen cycle’s completion is not present in
sufficient quantities in new tanks. Introducing fish into this
environment can be risky, though it can be done.
- Start
off with a small amount of fish. Do not stock your tank to capacity.
Start with hardier fish such as mollies or danios, and gradually add
your fish over the course of a month or two.
- Feed minimally.
Many fish owners overestimate the amount of food their fish need. Start
with a small pinch of food, and see whether your fish finish it. You can
always feed more, but it becomes more difficult to retrieve uneaten
food.
- Carefully monitor with a test kit. It is recommended that
you get a freshwater test kit with ammonia, nitrites, and nitrates for
this. High and even moderate levels of ammonia and nitrites can be toxic
to your fish, so it is important to test daily and then gradually
decrease.
- Change your water frequently. If you detect high
levels of ammonia or nitrites, do a partial water change of 20-50%.
Repeat any time necessary. Products such as Prime or Carbon Zeolite can
absorb or detoxify nitrites.
- Add a biological supplement (such
as Hagen’s Cycle) regularly. These supplements actually contain live
cultures of helpful nitrifying bacteria. You can add daily without worry
of overdose. This can significantly speed up the cycling of your
aquarium.
- When your tests read positive for nitrates, and
ammonia and nitrite levels decrease, your tank is cycled. At this point,
you can be a little more relaxed with your water testing and water
changes. Nitrogen cycling still occurs, but there should be less spiking
(unless you change something, such as adding new fish). Transition to a
regular aquarium maintenance schedule.
Starting the Cycle Without Fish
If
you have the time and patience, you can start the nitrogen cycle
without fear of losing fish. To start the nitrogen cycle before adding
your fish (so as to introduce fish into a more stable environment), you
can use a few simple methods.
- Fish food.
Add a few pinches of fish food into your aquarium regularly twice a day
(as if you were feeding your fish). Test your tank daily. When you get
nitrate readings, you can add fish. Make sure you also monitor phosphate
levels with this process, as many fish foods contain high levels of
phosphates (which can stimulate algae growth).
- Filter media/gravel from an established tank. To
speed up the nitrogen cycle, you can use some filter media or gravel
from a tank that has been running for a while. Transfer immediately and
“feed” your aquarium a small amount of fish food twice daily and test
for nitrates. When you get nitrate readings, (and decreased ammonia and
nitrite readings) you can add fish.
Both of these methods can still benefit from Cycle or Stability to speed the cycling.
