Fishless Cycling of the Aquarium

The Classic Approach

When setting up an aquarium, buy some cheap hardy fish and get the cycle started.
These fish have been given names like "Starter Fish". "Suicide Fish", "Disposables" and so on.

The purpose of these fish is to provide ammonia through respiration, fish waste, and decaying food. The ammonia allows the first set of nitrifying bacteria to colonize and to initiate the cycling of the tank.

During this time of cycling, ammonia and later nitrites will spike up to dangerous levels for the little creatures. Some of them survive the harsh welcome but will not live out their full potential. Of course a few exceptions are tolerated within this rule.

The cycle is complete as soon as ammonia and nitrite levels are nolonger measurable by test kits. This classical form of cycling takes anywhere from 30 to 45 days.

Using Pure Ammonia to Cycle

Instead of using fish food for ammonia production, we can also introduce pure ammonia to the tank. After the tank has been set up (see above), add 5 drops of ammonia per 10 Gallons into the water on a daily basis.

Ammonia will rise to 5 ppm and higher. As soon as nitrites are measurable, reduce the ammonia input to 3 drops per day. Nitrites will rise to similar levels. Keep adding 2-3 drops until the measurements of ammonia and nitrites come out with 0 ppm. The tank has then completely cycled. Seeding the tank can significantly enhance this process. 7 days for a complete cycle are not unheard of; otherwise this methods takes 2-3 weeks. The bacteria colonies, using this method, are certainly large enough to handle a well-stocked aquarium.