Unfortunately, nitrifying bacteria are some of the slowest growing bacteria in nature, and the cycling process can take as long as six weeks. There are a few things you can do to speed up this process, however.
Temperature – like most microorganisms, nitrifying bacteria multiply more quickly in warmer conditions. Their optimal temperature is between 77-86°F (25-30°C). If possible, try to keep water temperature within this range while startup cycling. At 64°F (18°C) their growth rates decrease by 50%. At 46-50°F (8-10 °C) it decreases by 75%, and stops all together at 39°F (4°C). It will die off at or below 32°F (0°C) and at or above 120°F (49°C).
Oxygen – Nitrifying bacteria are aerobic and will multiply much faster under highly oxygenated conditions. Even if you are cycling without fish be sure to have as much oxygen in your tank water as you would if the fish were there. Think of the bacteria as just another living organism that requires oxygen in your system.
Adding bacteria – You can “jump start” the process by adding bacteria from an existing colony. Good sources of beneficial bacteria are ranked here, leading with the best (the lower you go on the list the more chance you have of introducing a disease into your system):
- Microbe Lift Nitrifying Bacteria product (included with the AquaCycle Cycling Kits)
- Media from an existing aquaponic system.
- Filter material (sponge, biomedia, brushes, mats, etc.) from an established, disease-free aquarium.
- Gravel from an established, disease-free tank (Many local pet and aquarium stores will give this away if asked.).
- Other ornaments (driftwood, rocks, etc.) from an established aquarium.
- Squeezings from a filter sponge (any pet and aquarium store should be willing to do this…).
- Rocks from a backyard pond with fish in it.
- Rocks from a river, lake or wild pond.