No, snazy. Relative to ammonia there are no truly long term studies I have seen. And for the record this discussion is relative to the detectible levels of ammonia reltive to the hobby. the levels that are always there have no bearing on this discussion. No I have not seen anything at all for "low quality water" as that term would be way to nebulous to use for a search. How would you put a scientific definition on that? But then it doesn't take a genius to conclude that clean water is better for fish than dirty water. But this might not include dry and rainy season spawners- how bad does water get at the peak of the dry? But how did you jump from a discussion of ammonia levels to that? Perhaps that is an issue better left for another thread? So back to ammonia.
This is what makes looking at the literature so difficult. What I, and other folks looking at for the same reasons, have to do is try to extrapolate from the information that does exist and try to determine what may apply in our tanks. The most salient thing I have seen is that all of the information is always related to NH3. It will usually mention TAN levels as well. Occasionally, I see the reverse, but a never don't see HN3 levels stated. Next, almost all of them are in -Nitrogen scale. This is very important in what I have concluded relative to ammonia levels because the hobby kits use the total ion scale. Multiply the API ammonia result by 1.28 to get it equivalent to the same ppm on the Nitrogen scale.
So what do I see in general when I input a term like "Chronic Exposure to sub-lethal ammonia" or some similarly crafted search term? There are a lot of studies that involve other things that would not be in tanks. 1,810 returns
http
/scholar.google.com/scholar?start=0&q=Chronic+Exposure+to+sub-lethal+ammonia&hl=en&as_sdt=0,33&as_ylo=2000&as_yhi=2013
Here is what comes up for the 1st ten answers: 7 are abstract,s only and 3 are full studies
*- what one can see for free without some affiliation getting one access.
-Exposure of brown trout, (Salmo trutta), to a sub-lethal concentration of copper in soft acidic water: effects upon muscle metabolism and membrane potential
-The effects of acute and chronic ammonia exposure during early life stages of the gulf toadfish, (Opsanus beta)
-Sub-lethal effects of exposure of juvenile turbot to oil produced water
-Acute toxicity of ammonia and its sub‐lethal effects on selected haematological and enzymatic parameters of mrigal, Cirrhinus mrigala (Hamilton)
(In natural environment it attains a length of 99 cm and weight of 12.7 kg)
-Ecotoxicology of carbon-based engineered nanoparticles: Effects of fullerene (nC60) on aquatic organisms
(HUH?)
-Complex physiological traits as biomarkers of the sub-lethal toxicological effects of pollutant exposure in fishes
*
-Effects of ammonia on juvenile silver perch (Bidyanus bidyanus
* (In my list above)
-Growth, stress response and free amino acid levels in Senegalese sole (Solea senegalensis Kaup 1858) chronically exposed to exogenous ammonia
-Ammonia toxicity in fish
-Effect of sub-lethal diazinon concentrations on blood plasma biochemistry
*
One of those was in my above post. As you can see each page will contain slim pickings relative to for what we are searching.
But lets consider the most promising title of those- Ammonia toxicity in fish. First here is what you see on the results page:
Ammonia toxicity in fish
DJ Randall, TKN Tsui - Marine pollution bulletin, 2002 - Elsevier
... Derived criteria are based on acute and
chronic toxicity studies (Stephan et al., 1985).
... to survive
both high
ammonia levels in the water and terrestrial
exposure by actively
... Plasma
ammonia
concentration in brown trout (Salmo trutta) exposed to
sub-
lethal copper concentrations
...
Cited by 246 Related articles All 5 versions Cite
But I click through anyway knowing it was just an abstract, the abstract contained some incorrect assumptios/statements which I have high lighted in red below:
Abstract
Ammonia is present in the aquatic environment due to agricultural run-off and decomposition of biological waste. Ammonia is toxic to all vertebrates causing convulsions, coma and death, probably because elevated NH4+ displaces K+ and depolarizes neurons, causing activation of NMDA type glutamate receptor, which leads to an influx of excessive Ca2+ and subsequent cell death in the central nervous system.
Present ammonia criteria for aquatic systems are based on toxicity tests carried out on, starved, resting, non-stressed fish. This is doubly inappropriate. During exhaustive exercise and stress, fish increase ammonia production and are more sensitive to external ammonia. Present criteria do not protect swimming fish. Fish have strategies to protect them from the ammonia pulse following feeding, and this also protects them from increases in external ammonia, as a result starved fish are more sensitive to external ammonia than fed fish.
There are a number of fish species that can tolerate high environmental ammonia. Glutamine formation is an important ammonia detoxification strategy in the brain of fish, especially after feeding. Detoxification of ammonia to urea has also been observed in elasmobranches and some teleosts. Reduction in the rate of proteolysis and the rate of amino acid catabolism, which results in a decrease in ammonia production, may be another strategy to reduce ammonia toxicity. The weather loach volatilizes NH3, and the mudskipper, P. schlosseri, utilizes yet another unique strategy, it actively pumps NH4+ out of the body.
So what does seeing all of this tell us. The statement in red are not really material to the results (if obtained and analyzed properly) if they are or are not true. But there are similar statements there that I read in a lot of other studies:
-During exhaustive exercise and stress, fish increase ammonia production and are more sensitive to external ammonia.
(The stress part especially)
-as a result starved fish are more sensitive to external ammonia than fed fish
-There are a number of fish species that can tolerate high environmental ammonia.
I really have read 100s of these things. I have read all or as much as I could of what I found. And over time things started to line up.
What I know is this:
+ There is virtually no research I can find that specifically deals with cycling tanks. If anyone can find some, please provide links.
+The common hobby test kits measure in total ions and the research is expressed in the nitrogen scale. This creates a further buffer between the readings on the hobby kits and the danger levels found in research studies stated on the Nitrogen scale.
+ The critical factor in almost every study is NH3-N not TAN.
+ The levels in most research tests are either well above 1-2 ppm on an API kit and/or for longer periods than I would advocate allowing ammonia to remain unchallenged.
+Fish can tolerate some detectible level of ammonia for some period of time and sustain no long term damage. the issue is one of how much and how long.
+Fish may experience a small amount of damage from mostly safe ammonia exposures that will not self correct. However, it would be very difficult to show that such damage would actually shorten the total life expectancy of that fish in a tank. Many other things might do worse harm long before then. This is especially true for us all as newbies. So I see some further wiggle room here for defining long term harm actually happening to a fish in the tank of a newbie. Fish in tanks live pretty cushy lives.
+Just because one does many water changes to keep ammonia levels down doesn't mean they are not increasing stress enough to counter that to some extent or even make things worse? I am not sure where the answer lies. There is no research on this either as far as i have seen.
+Going the frequent large water change route to hold ammonia levels very low for a substantially longer time than fish would be exposed to ammonia at 1-2 ppm of TAN on hobby kits also has consquences. I suggest this maybe as potentially harmful or even more harmful due to the duration factor. I am not sure if it would be less but it could be, how much nobody can say as far as i have seen. There is absolutely 0 research on this topic.
My take on ammonia toxicity and fishless cycling is really a conglomeration of what I have read on the subject much more than it is the result of any single piece or list of them. Not only is it based on what I have seen, it is also based on what I have not. Even when you run the API numbers at 82F (27.7C) for .25 and .50, ppm here is what you get: for ppm of NH3.
pH 7.0 .0018 and .0036
pH 7.5 .0056 and .0111
pH 8.0 .0168 and .0336
pH 8.5 .0464 and .0928
If you want to argue pH 8.5 is a problem I agree over .25 ppm. But how many beginner tanks are at that pH and temp? And I would modify suggestions for 8.5 pH as opposed to the other levels. I would usually tell folks not to cycle at that pH with fish without doing heavy bacteria seeding. Tell me for what level of total ammonia can you show that .02 ppm or lower levels of NH3 at any TAN is considered a danger by anyone anywhere in the literature. As one crosses over .02 the salmonids come into play, but they make for an unreasonable comparison. With a diverse number of researchers and professionals focusing on the .05 ppm NH3 line, I feel something just below that to be a pretty reasonable place to draw a line for fish in cycling. And to be safe I tend not to suggest TAN be allowed to get beyond 2.0 in any situation. I have 0 evidence that this number represents the danger point even if the NH3 level is safe. I just see no need to ever get any higher than this. And I do not suggest folks allow ammonia levels between 1 and 2 ppm to persist beyond between 1 and 2 weeks based on the situation.
If you or anybody else can cite some studies, research or other equally reputable information contrary to my position, I will gladly revise my opinion on this. If I found them myself I would not have reached the conclusions I have. Nor can I find anything about ammonia at a pH levels below 6.0 where NH3 is never a factor. If anybody else can, please provide links.
I just wanted you to know that I am not argueing that any level of ammonia is harmful. Obviously there's always ammonia in a fish tank to an extent. I am not certain about the maximum levels not harmful to different species either. I am sure your articles above will have a lot of info about that. However, is there any scientific experiment for example that you have come across and it was held for a few months to a year or the lifetime of the fish to show the secondary effects low quality water can have on fish despite not being lethal directly in certain scanarios?
