Now during the cycling process certain bacteria convert ammonia into nitrite, and at various stages both of these elements build to highly toxic levels, which endangers the lives of the animals. Do you see the catch 22 here? If fish are needed as the source of ammonia to start the cycle, and during the process the ammonia and nitrites reach toxic levels that put them in harms way, which many aquarists do not want to do, how can you cycle the tank "without" the fish?
Tank Cycling Options
- Add some hermit and/or true crabs instead. They are pretty hardy animals, rather inexpensive, and will cycle your tank just as well as fish do. Besides, they can be pretty entertaining critters to have.
- Cycle the tank with live rock and/or live sand. These are both living parts of the reef that produce waste. Not only will they cycle the aquarium, they become the main source of biological filtration itself.
- Add ammonium chloride. Read John Tullock's " Cycling the Tank" article, or refer to Martin A. Moe, Jr.'s "The Marine Aquarium Handbook: Beginner to Breeder" ( read review & compare prices) for step-by-step instructions on how to use this cycling method.
- This may sound a little off the wall, and people have done it, but you can use human urine as the ammonia source.

