Tolak- the link in the thread here is is a dead one. It took me a while to track it down.
http
/nsgd.gso.uri..../ilinw91001.pdf This is dated 1991, before the discovery of either the AOB or NOB strains that actually do the work in our tanks. Moreover, the authors say this:
Our best estimate for the collective impacts of decay, endogenous metabolism, death, and predation on nitrifiers presently ranges from 0.05 to 0.12 days -1. Correspondingly, these rates imply that resting, non-active nitrifiers will deteriorate at rates of 5 to 12% per day.
However, these values were typically inferred from heterotrophic bacteria rather than specifically measured for nitrifiers. Hence, conclusive data to clarify our understanding of nitrification-related decay and death is lacking.
So you are citing as proof something the authors themselves say is not proof, merely inference.
The link to the Magazine article and the other research paper both support what I say rather than your contention about 10-12% of the bacteria dying daily. They say just the opposite in fact.
Moreover, the second study you link to, while informative, deals with waste water treatment and different strains of bacteria than oxidize ammonia in our tanks. The ones we develop for the long term are a different strain:
Enrichments of the AOB strains were added to newly established aquaria to determine their ability to accelerate the establishment of ammonia oxidation. Enrichments containing the Nitrosomonas marina-like AOB strain were most efficient at accelerating ammonia oxidation in newly established aquaria. Furthermore, if theNitrosomonas marina-like AOB strain was present in the original enrichment, even one with other AOB, only the Nitrosomonas marina-like AOB strain was present in aquaria after nitrification was established.
From
http/aem.asm.org/c...1.full.pdf+html
What I did take away from the article (which I have read before) are the following two tidbits:
1. "This indicates that the recovery process of Nitrosomonas europaea is complex and might depend on external factors such as
growth conditions and the physiological state of the cell prior to starvation"
This would imply that there are no hard and fast rules for time as the condition of the bacteria at the outset etc. can greatly effect this.
2. "Although the recovery after short-term starvation for other AOB strains, for example members of the Nitrosomonas oligotropha cluster or Nitrosospira briensis, is very fast as well, there are considerable differences among AOB strains in recovery after long periods of starvation."
This would imply that one would have to look at each strain to know what the relative recovery rate factor might be for that specific strain.
So this study does look at the different recovery times for a variety of strains and shows they can differ greatly, but it did not look at the specific strain that seems to dominate in our tanks. I saw nothing in this article to support your contention.
Furthermore, if you search my posts you will find links to research showing soil based AOB that survived for decades in a dry environment. Granted it was a small amount, but it was still found to be viable after all that time.
What the PFK article does is say the very same things I have been posting on this site for some time now which is in direct contradiction to what many members here state and most of what is posted in the site's cycling "sticky". I have contended for a while that the article on this site re fishless cycling is perhaps one of the most misinformed ones I have seen on any fish site. I can also say that there are more threads here on problems with fishless cycles than I have seen anywhere else (relative to membership numbers). I have cycled over 50 tank fishlessly and not a one ever stalled. I have never seen so many threads about stalled cycles as I have here. It is almost a first for me.
I believe that until that article is rewritten or replaced, these problems will continue to occur for new fish keepers who try to follow the advice. If you read the final part of the PFK article you linked us to, you will read this:
Anecdotally speaking, much of what the research tells me strikes a chord with practices that I've engaged in for years. As someone who values the biological benefits of old media and substrates, even after several weeks, and as someone who never has issues with ammonia in any new set up, I'm forced to wonder – just what is it that so many new fishkeepers are doing to get ammonia through the roof?
Maybe they are reading and following the fishless cycling article here, among other thing?
Members here should understand that I am stating my opinions which I believe are based on the published scientific facts. These are the facts which I often quote and to which I provide links. I am more than willing to alter those opinions whenever presented with scientific evidence to the contrary.
