Hi all,
The microbial activity you're talking about will come along too. It is just an NH4 containing bottle....One can think of it as a fertilizer. There's ammonia in tanks all the time...and the actual ammonia cycle period during fishless cycling is about a week.... but it takes a couple more for nitrites to start rapidly being converted....no damage done to a fishless tank whatsoever and the actual maturity of a tank, after nitrification is efficient, takes months..
Yes, but it is back to the shades of grey argument. When you add filter material from an established system you have added a bacterial supplement that is appropriate for your water, as long as you have reasonable levels of dissolved oxygen, that initial microbial supplement will offer a flexible response to the changing nutrient supply. I don't see it as a binary switch between "non-cycled" and "cycled", I don't actually think that "cycled" is a very useful concept. Stephan Tanner explains the time scale for the development of a fully functioning ecosystem in <"
Aquarium Biofiltration">.
You can cycle a filter with ammonia, and then measure the relative levels of NH3, NO2- & NO3-, add all your stock, and then rely on microbial filtration from a canister filter. It is possible, and plenty of people do it, but you are always balanced on razor edge where any sudden increase in the bioload, or loss of dissolved oxygen, is likely to lead to a positive feed-back loop where ammonia levels rise in the tank. Once you've added plants, and a substrate, you don't have a single point of failure.
Once our tank is established we are back to Liebig's law of the minimum, one resource will limit each organisms potential growth and levels of the main nutrients (in microbial terms "the substrate"), nitrogen, carbon, oxygen etc will regulate the microbial community.
And it doesn't need a lot of bioload to multiply. People who sport and use water bottles or have pets with drinking bowls experience this biofilm forming within days if the bottle or bowl is not cleaned before every refill. Throwing plants and wood and soil in the tank is enough to speed this process up.
Yes this is also a good point, the traditional view is that only a very specialized suite of bacteria perform nitrification, and that they have specific requirements, which must be fulfilled for them to function. But, we know that this isn't actually the case, partially because the ammonia oxidising bacteria that were assumed to provide this role in aquariums (they were isolated from sewage treatment) are, at most, minor players.
I can't get full-text of this paper <"
Microbial Succession and Nitrogen Cycling in Cultured Biofilms as Affected by the Inorganic Nitrogen Availability">, but the abstract suggests that nitrogen deficient systems are more diverse and flexible;
Biofilms were cultured using a flow incubator either with replete inorganic nitrogen (N-rep) or without exogenous inorganic nitrogen supply (N-def). The results showed that the biomass and nitrogen and phosphorous accumulation of biofilms were limited by N deficiency; however, as expected, the N-def biofilms had significantly higher microbial diversity than that of N-rep biofilms. The microbial community of biofilms shifted in composition and abundance in response to ambient inorganic nitrogen level.
cheers Darrel