This is taken from one of the links.
Minimizing Fish Stress During Initial Cycling
Should ammonia levels become high during the cycling process, corrective measures will need to be taken to prevent fish deaths. Most likely, you will simply perform a sequence of partial water changes, thereby diluting ammonia to safer concentrations.
As a final caution, several commercial products (e.g., ``Amquel'' or ``Ammo-Lock'') safely neutralize ammonia's toxicity. Amquel does not remove the ammonia, it simply neutralizes its toxicity. Biological filtration is still needed to convert the (neutralized) ammonia to nitrite and nitrate. Thus, adding Amquel causes the ammonia produced by the fish to be neutralized instantly, yet still allows the nitrogen cycle to proceed. Using Amquel during the cycling phase has one significant drawback, however. Amquel (and similar products) may cause ammonia test kits to give false readings, making it difficult to determine exactly when cycling has completed. See the TEST KIT SECTION for details.
It is also possible to cycle a tank without ever adding fish. The role fish provide in the cycling process is simply their steady production of ammonia; the same effect can be achieved by adding chemical forms of ammonia manually (e.g., ammonium chloride). However, it is a bit more complicated than using fish because the water chemistry needs to be monitored more closely in order to add the proper amount of ammonia on a day-to-day basis.
/www.thetropicaltank.co.uk/cycling2.htm
