Cycling
Cycling - the process of fostering nitrifying bacteria (known as 'biofilter') that help filter out toxic waste in the nitrogen cycle, ensuring that the aquarium remains a healthy environment. The biofilter consumes food and waste that produce toxic ammonia, as well as breaking down existing ammonia to less-toxic nitrites
One way to keep the biofilter alive is to ensure untreated tap water never touches your aquarium, as it contains chlorine and chloramines
Following either of these sets of steps to kick-start your biofilter
Fishless Cycle
Things needed
- Ammonia (pure NH4Cl)
- Aquarium test kit
- Fish food
Steps
- Test the water pH, as a pH <7 can slow down or stop the cycling process
- If using tap water, add any dechlorinating agents you have
- Now, you can either:
- Ghost-feed your tank, adding food that you would give to the amount of fish you intent to keep. The uneaten food breaks down and produces ammonia, starting the cycle
- Use ammonium agents to add ammonia directly. Add ammonia according to your tank's liquid capacity, in 3mg/L, or 3ppm. If using an ammonia badge, you can add little by little until it is in the 'toxic' zone
Fish-in Cycling
Recommended only for experts!Simply add a few fish. This is to ensure less waste is produced, so the water is unlikely to become toxic. Limit the amount of food, at least at first. This reduces waste produced, as well as uneaten food, reducing toxins produced
During the process, you should change the tank's water every few days, by replacing 10-25% of its water with fresh water. If its a saltwater tank, you'll need to add more saline.
Remember to check the toxic ammonia & nitrate levels with a water testing kit. Check on the water every few days, ensuring ammonia stays <0.5mg/L and nitrate stays <1mg.
Once ammonia & nitrate levels drop to/near zero, the cycling process is complete, and your biofilter is live. Now, you can add fish slow, 1/2 at a time, with a week or more between each addition.