[pop]

By general consensus most folks at this site believe the need for water changes is due to the continual corruption of water quality by ontogeny. This defiling of water purity apparently is the result of TDS or total dissolved solids that can only be removed by changing aquarium water or some sort of membrane filter. When TDS are not removed then all sorts of terrible events begin to occur like ph crashes, elevated levels of nutrients such as phosphate and sulfates and I think possibly nitrates. It is important to remember that fish in a TDS saturated environment will have their internal systems taxed in a negative manner. One can conclude that TDS is a very bad thing especially for the happy healthily fish crowd (1).

The general view is that using a tds meter is the only way to determine or measure the levels of tds. TDS meters test the electrical continuity of the sample because pure water will not conduct electrical current therefore only TDS will provide electrical continuity. This leads to the question are all total dissolved solids capable of electrical continuity. Will nitrate or chloride ions or ammonia anon conduct electricity?

In fact what is considered a safe level of TDS.
Some folks will say Fresh water by definition contains no more than 1500 mg/l of TDS (2). I was not able to locate any definition of fresh water tds measurements other than the federal government recommended maxim level of 500 ppm (3).

When I searched for the meaning of TDS (there is a good one in the article Total Dissolved Solids (2)) there is also another notion of tds and that is water purity.

What is the meaning of purity? The first definition is chastity; another could be clearness of thought or expression or one might consider the notion of purity as a visual or optical clearness the ability to see through something.


Total Dissolved Solids
The measure of the combined content of all inorganic and organic substances. ….Primary sources of TDS in water come from natural sources, sewage, urban run-off, industrial wastewater, and chemicals used in the water treatment process. A high concentration of TDS does not pose a health risk but it does affect the aesthetic quality of the water, (4).
The Secondary Drinking Water Regulations control contaminants in drinking water that primarily affect the aesthetic qualities of water. Several of these -- chloride, sulfate, total dissolved solids -- are ionized contaminants. Color and odor are contaminants which cause objectionable sensory responses to the water.(5)

Since total dissolved solids is a measurement of aesthetic clearness of water and not a measurement of pollutants or a rating of healthiness of water. Why are there secondary standards? EPA believes that if these contaminants are present in your water at levels above these standards, the contaminants may cause the water to appear cloudy or colored, or to taste or smell bad. This may cause a great number of people to stop using water from their public water system even though the water is actually safe to drink.(6)
Water quality is a tuff issue as pointed out in other post and sometimes meaning can become clouded yet I can not clearly see how a measurement of aesthetic qualities of water (Total Dissolved Solids) be logically transferred to the terrible events of doom and destruction that has been projected by the ones who know.
One would think moderators and experienced fish keepers would know that TDS is a measurement of aesthetic qualities of water not contamination.
When moderators and others who know, post incomplete and misguided post, articles and opinions is it just a delightful distortion of facts?
is …….THERE AN EVIL lurking OUT THERE that only can be seen by the shadow.
Read more:
(1) http://www.tropicalfishkeeping.com/...on-water-changers-crowd-126655/#ixzz2JwT5qLM1

(2) http://www.tropicalfishkeeping.com/...al-solids-tss-tds-freshwater-aquarium-122027/

(3) Water Quality Terms and Definitions | The Official Website for the City of Tucson, Arizona

(4) Glossary | APEC Water

(5) What is TDS and its relation to water? | APEC Water

(6) Secondary Drinking Water Regulations: Guidance for Nuisance Chemicals | Drinking Water Contaminants | US EPA


http://dictionary.reference.com/browse/purityhttp://dictionary.reference.com/browse/purity

pop

 

[1077]

It seem's all has been answered in first paragraph Pop, if primary concern is fishes health.
Been at this hobby for a long time and tried the no water change's that some seem to favor (largely out of laziness).
Not until you have seen the result's from both ...can one appreciate the benefit's of clean water.
TDS and what it may or may not represent as far as health risk to human's is well...much ado about nothing from this hobbyist's standpoint.
Is the fishes that are my responsiblity and over the year's,,I have found that they do indeed thrive in clean water (regular water changes).
You, and other's may do as you wish but for me and many many other's, the fifteen minutes a week it takes to perform a water change ain't nothin and provides much better result's than the few to no water changes I tried early in the hobby when it was believed that old water was more stable.
Ain't till you try and add new fishes to the old water that one start's to grasp the benefit's of regularly removing dissolved organic's and replacing them with clean water.

 

[pop]

Hello you seem to have missed the boat 1077 & thekoimaiden:

I was not pointing to changing water because it is needed I was pointing out that total dissolved solids measure only the aesthetic aspects of water and these considerations are taste and smell of the water as well as how clear the water is, that is all that TDS measures.

There are much better standards to indicate the presents of pollution and contamination of aquarium water or drinking water. If you are concerned with nitrates would you think using a standard that measures aesthetic qualities of the water column appropriate or would you use a nitrate test kit that will provide a more accurate measure.

I have a strong suspicion that you folks would go for the nitrate test kit as I would because TDS value would not provide the actual concentrations of nitrate; though TDS value will indicate if the aquarium water smells or taste bad or the water column lacks clarity.

Again total dissolved solids only measure the aesthetic aspects of water. Folks that think different have been sold a bill of goods that is composed of misinformation, incomplete and ill thought-out notions.

Show me the science and facts that oppose the factual base for the definition and uses I have provided for TDS.

…….THERE AN EVIL lurking OUT THERE that only can be seen by the shadow.



pop

 

[Byron]

When I searched for the meaning of TDS (there is a good one in the article Total Dissolved Solids (2)) there is also another notion of tds and that is water purity.

What is the meaning of purity? The first definition is chastity; another could be clearness of thought or expression or one might consider the notion of purity as a visual or optical clearness the ability to see through something.

Total Dissolved Solids
The measure of the combined content of all inorganic and organic substances. ….Primary sources of TDS in water come from natural sources, sewage, urban run-off, industrial wastewater, and chemicals used in the water treatment process. A high concentration of TDS does not pose a health risk but it does affect the aesthetic quality of the water, (4).
The Secondary Drinking Water Regulations control contaminants in drinking water that primarily affect the aesthetic qualities of water. Several of these -- chloride, sulfate, total dissolved solids -- are ionized contaminants. Color and odor are contaminants which cause objectionable sensory responses to the water.(5)

Since total dissolved solids is a measurement of aesthetic clearness of water and not a measurement of pollutants or a rating of healthiness of water. Why are there secondary standards? EPA believes that if these contaminants are present in your water at levels above these standards, the contaminants may cause the water to appear cloudy or colored, or to taste or smell bad. This may cause a great number of people to stop using water from their public water system even though the water is actually safe to drink.(6)
Water quality is a tuff issue as pointed out in other post and sometimes meaning can become clouded yet I can not clearly see how a measurement of aesthetic qualities of water (Total Dissolved Solids) be logically transferred to the terrible events of doom and destruction that has been projected by the ones who know.
One would think moderators and experienced fish keepers would know that TDS is a measurement of aesthetic qualities of water not contamination.
When moderators and others who know, post incomplete and misguided post, articles and opinions is it just a delightful distortion of facts?
is …….THERE AN EVIL lurking OUT THERE that only can be seen by the shadow.

This is very inaccurate. TDS is well defined in my article on the subject, and it has nothing whatever to do with water clarity or what is defined above as "purity." These definitions from public health water sources are not directly applicable to the issue in aquaria, which I would have thought was obvious to most. The drinking water that comes out of the tap--which we will assume for our purposes here is chlorinated-- is safe to drink; but it is not safe for fish. Put a fish in a tank of this tap water and within seconds it will be dead. This has nothing to do with TDS.

Since reading the articles poses so much difficulty, here is the definition:
Total Dissolved Solids (TDS) is a measure of the combined content of all organic and inorganic substances contained in the water in molecular, ionized or micro-granular (colloidal sol) suspended form. Generally the operational definition is that the solids must be small enough to survive filtration through a sieve the size of two micrometer.


TDS affect fish, to varying degrees depending upon the species. The rest is in the article.

 

[Mike]

I was not pointing to changing water because it is needed I was pointing out that total dissolved solids measure only the aesthetic aspects of water and these considerations are taste and smell of the water as well as how clear the water is, that is all that TDS measures.

Even if it were the case that TDS measured "only the aesthetic aspects of water", could you not use the degradation of the aesthetic aspects of the water as an indication that it's suitability for live aquaria was degrading as well?

I may not know exactly what's going on if I walk into a room and find the air has a green tint and a foul smell, but you can bet I wouldn't leave my kids in it.

Regarding your comment,

One would think moderators and experienced fish keepers would know that TDS is a measurement of aesthetic qualities of water not contamination.
When moderators and others who know, post incomplete and misguided post, articles and opinions is it just a delightful distortion of facts?

Moderators here were members first and remain members after they become moderators. When moderators here make substantive, aquaria related posts, they do so in their capacity as members. Our moderator status only comes into play when it comes to maintaining the site and addressing issues. For that reason, the substantive, aquaria related posts moderators make in their personal capacity should not be held to any higher standard than any other members'. That said, we're fortunate to have some pretty knowledgeable moderators. ;-)

 

[Mikaila31]

One would think moderators and experienced fish keepers would know that TDS is a measurement of aesthetic qualities of water not contamination.
When moderators and others who know, post incomplete and misguided post, articles and opinions is it just a delightful distortion of facts?

https://i.chzbgr.com/maxW500/7026683648/hAC23632A/

 

[1077]

Hello you seem to have missed the boat 1077 & thekoimaiden:

I was not pointing to changing water because it is needed I was pointing out that total dissolved solids measure only the aesthetic aspects of water and these considerations are taste and smell of the water as well as how clear the water is, that is all that TDS measures.

There are much better standards to indicate the presents of pollution and contamination of aquarium water or drinking water. If you are concerned with nitrates would you think using a standard that measures aesthetic qualities of the water column appropriate or would you use a nitrate test kit that will provide a more accurate measure.

I have a strong suspicion that you folks would go for the nitrate test kit as I would because TDS value would not provide the actual concentrations of nitrate; though TDS value will indicate if the aquarium water smells or taste bad or the water column lacks clarity.

Again total dissolved solids only measure the aesthetic aspects of water. Folks that think different have been sold a bill of goods that is composed of misinformation, incomplete and ill thought-out notions.

Show me the science and facts that oppose the factual base for the definition and uses I have provided for TDS.

…….THERE AN EVIL lurking OUT THERE that only can be seen by the shadow.



pop

I beg your pardon,,I believe it is you that is lost if as you say ..you can find no science or literature.
Quick search on the internet... Google..
"Effect's of Total dissolved Solid's on Aquatic life" plenty of such info exist's.(scientific studies).
Plenty of folk's breeding soft water species of fishes,and other's who breed very expensive Shrimp' s, some selling for as much as 100.00 dollar's a piece,take pain's to keep TDS as low as possible.
Hard water species more forgiving.

 

[pop]

Hello tropical fish keeping community:

I must recapitulate my previous post in this thread and must say I have fallen victim to my own predetermined notions after reviewing the science and facts that I requested.

Thank you all for getting my ducks in a row.

Though what I read about tds toxicity leaves some questions such as is there any studies for the toxicity of tds in aquariums? Most of the facts seems to be related to game and food species of fish and are representative of general problems with reproduction such as Harding of eggs and fertilizing eggs. Not shorting of life span in salmon or trout ect.

SUMMARY OF RESEARCH
No adverse effects were seen in either the embryo (1,961 mg/L synthetic effluent) or the swim-up fry test (2,080 mg/L) when exposed to 100% synthetic effluent.
No adverse effects were seen in % survival of chironomid larvae when exposed to full strength Red Dog Mine synthetic effluent (2,089 mg/L TDS), although growth was apparently reduced by about 45% in the same solution. No adverse effects were observed in chironomid larvae exposed to 1,134 mg/L TDS.
Reduced survival of Chironomidae larvae occurred at 1,750 mg/L and 2,240 mg/L, but not at 1,220 mg/L TDS. No growth effects were observed at any exposure level.



http://www.adfg.alaska.gov/static/home/library/pdfs/habitat/01_06.pdf

tds toxicity appears to have different effects on different life forms and sometimes no effect depending on the stage of development. Is there a difference between synthetic effluents used and actual tds found in the home aquarium?

Is it correct to think that after many generations of adaption to levels of tds a life form may need specific levels of tds to survive? If this is the case is it really toxic.

I am not sure that I agree with the science of tds. Since no conclusions can be determined about the reported effects of tds concentrations, were the effects the result of high tds levels or the sudden change in tds or absence of exposure time to synthetic tds solutions but I will no longer contest it.

….. there an evil lurking out there somewhere that can only be seen by the shadow.

pop

 

[Byron]

My article went into all this and answered the questions. And you will note in the References that the sources used were all related to aquarium fish scientists and experts.

Aside from that, there is the common sense aspect. Fish "adapt" by evolution over thousands of years. Soft water fish live in water with zero or near-zero TDS. It simply defies logic to expect them to be at their best in anything other than very similar water. The many effects of inappropriate water parameters is detailed in the article.

http://www.tropicalfishkeeping.com/...al-solids-tss-tds-freshwater-aquarium-122027/

 

[1077]

My article went into all this and answered the questions. And you will note in the References that the sources used were all related to aquarium fish scientists and experts.

Aside from that, there is the common sense aspect. Fish "adapt" by evolution over thousands of years. Soft water fish live in water with zero or near-zero TDS. It simply defies logic to expect them to be at their best in anything other than very similar water. The many effects of inappropriate water parameters is detailed in the article.

http://www.tropicalfishkeeping.com/...al-solids-tss-tds-freshwater-aquarium-122027/

I'm with you Byron.
Are two approaches to take in my view.
(1) Try and determine at what rate the accumulative effect's of TDS take a toll on particular species at differing times of fishes development, and keep level's below this (water changes,chemical filtration)
(2)Keep level's as low as possible to protect ALL species.
The second approach seem's the easiest to implement and safest approach for aquarium fishes,invert's.

 

[pop]

Hello admin:

I liked the metaphor ..” I may not know exactly what's going on if I walk into a room and find the air has a green tint and a foul smell, but you can bet I wouldn't leave my kids in it. “

my answer would be a little different as to I would say to my kid go on in an have fun and don’t ask for money. You see his girl friend has blue hair and they would be at home.

This is another good point ‘Even if it were the case that TDS measured "only the aesthetic aspects of water", could you not use the degradation of the aesthetic aspects of the water as an indication that it's suitability for live aquaria was degrading as well?”
That’s just what I do ……. Change the water when the aesthetic aspects of the water are degraded.

I must also admit to debased behavior in regard to remarks about moderators, you are right I gave them greater credit and knowledge than I should have not implying anything about their experience.

I have read this article and the cited references Total Solids (TSS and TDS) in the Freshwater Aquarium. I still did not see any real verified facts nor was there any clear cause and effect relationships. There are observations and speculations about specific events without viable conclusions that prove high levels of tds caused the event due to the event might have been caused by the sudden change of concentrations of tds. Some of the specific events could be accounted for by sudden changes in temp, ph or the nitrogen cycle.

Show me the science and verifiable fact that establishes cause and effect relationship that TDS causes the specified event. The problem as I see it is something else than TDS could cause the same effect and that has to be eliminated before cause and effect relationship maybe established.

Is ……. There an evil that is lurking out there somewhere that can only be seen by the shadow……

pop

 

[Byron]

I have read this article and the cited references Total Solids (TSS and TDS) in the Freshwater Aquarium. I still did not see any real verified facts nor was there any clear cause and effect relationships. There are observations and speculations about specific events without viable conclusions that prove high levels of tds caused the event due to the event might have been caused by the sudden change of concentrations of tds. Some of the specific events could be accounted for by sudden changes in temp, ph or the nitrogen cycle.

The whole article was verified scientific fact. If you choose not to believe it, so be it. But I wish you would go and argue this with the biologists and not me. They would be better qualified. I just accept their concensus since they know more about this than I do--or you for that matter. You probably don't listen to your doctor either. I tend to accept that these people have the knowledge and I would be foolish to disregard it.

Show me the science and verifiable fact that establishes cause and effect relationship that TDS causes the specified event. The problem as I see it is something else than TDS could cause the same effect and that has to be eliminated before cause and effect relationship maybe established.

It is true that many factors can affect the fish's physiology and health. TDS is just one, and it does cause what I stated in the article. That is scientific fact, period.

 

[Romad]

https://i.chzbgr.com/maxW500/7026683648/hAC23632A/

Grumpy Cat has joined the thread Too funny!

 

[1077]

Hello admin:

I liked the metaphor ..” I may not know exactly what's going on if I walk into a room and find the air has a green tint and a foul smell, but you can bet I wouldn't leave my kids in it. “

my answer would be a little different as to I would say to my kid go on in an have fun and don’t ask for money. You see his girl friend has blue hair and they would be at home.

This is another good point ‘Even if it were the case that TDS measured "only the aesthetic aspects of water", could you not use the degradation of the aesthetic aspects of the water as an indication that it's suitability for live aquaria was degrading as well?”
That’s just what I do ……. Change the water when the aesthetic aspects of the water are degraded.

I must also admit to debased behavior in regard to remarks about moderators, you are right I gave them greater credit and knowledge than I should have not implying anything about their experience.

I have read this article and the cited references Total Solids (TSS and TDS) in the Freshwater Aquarium. I still did not see any real verified facts nor was there any clear cause and effect relationships. There are observations and speculations about specific events without viable conclusions that prove high levels of tds caused the event due to the event might have been caused by the sudden change of concentrations of tds. Some of the specific events could be accounted for by sudden changes in temp, ph or the nitrogen cycle.

Show me the science and verifiable fact that establishes cause and effect relationship that TDS causes the specified event. The problem as I see it is something else than TDS could cause the same effect and that has to be eliminated before cause and effect relationship maybe established.

Is ……. There an evil that is lurking out there somewhere that can only be seen by the shadow……

pop

Nope,,the burden is on you to prove YOUR point,and that the Science is flawed, which you have thus far,, failed miserably to do.
In a properly maintained,stable,cycled aquarium, there is not likely to be any sudden changes to the system save the self inflicted.:roll:
Is well known among expierienced hobbyist's,scientist's, that 80 to 90% of all fish health problem's we see in the aquarium, can be directly tied to water quality or a lack thereof.
Stand's to reason for those reasonable, that weekly water changes are best,and fastest way to ensure that organic input in glass box of water does not rise to level's that may increase stress related Illness by weakening immune system.
Few people I know, are interested in how much of excess waste allowed to collect in closed system does it take, before aquatic life begin's to show the effect's.
Certainly not how much it takes to kill the fish outright.
Glass box of water with daily input, fish food's,fish waste, and no export mechanisim,will eventually have negative effect on the life therein.
No one you know ,or I know, ever lost fishes by performing water changes to keep metabolites,conductivity,TDS,NitrAtes,at negligible levels.
Plenty of folk's have killed fish by not doing so.

 

[pop]

pop's responce tds

Hello 1077 and the TDS gang;

I don’t believe I said that the science was/is flawed in the tds article. What I said is that there is a significant lack of scientific facts presented and the manner the facts are presented leave more questions than provided answers. I believe you stated that ‘biologist …. . They would be better qualified. I just accept their consensus since they know more about this than I do--or you’ I am not sure that all scientist and their reports are valuable or truthful.
Since you and Bryon place such faith in published facts then consider:

Jan Henrik Schön , a researcher at Bell Laboratories in New Jersey, had five papers published in Nature and seven in the journal Science between 1998 and 2001, dealing with advanced aspects of electronics. The discoveries were abstruse, but he was seen by many of his peers as a rising star. In 2002, a committee found that he had made up his results on at least 16 occasions, resulting in the public embarrassment of his colleagues, his employer, and the editorial staffs of both the journals that accepted his results. Schön, who by then was still only 32, said: “I have to admit that I made various mistakes in my scientific work, which I deeply regret.” Nature also reported him as adding in a statement, “I truly believe that the reported scientific effects are real, exciting and worth working for.” He would say no more.
Shinichi Fujimura was one of Japan’s leading archaeologists – despite being self-taught. In 1981 he made his first discovery of stoneware that dated back 40,000 years. It was the oldest stoneware ever found in Japan and this discovery launched his career. During the following years he discovered older and older artifacts that pushed the limits of Japan’s known pre-history.
On October, 2000, Fujimara discovered a cluster of stone pieces that they believed to have been made by primitive people; they also found several holes that they claimed were to hold supports for primitive dwellings. The find was believed to be over 600,000 years old – making the oldest signs of human habitation in the world. This lead to international coverage.
Then, on November 5, the Mainichi Shimbun newspaper published three photos on the front page, which showed Fujimara digging holes at the site and burying the artifacts that he later dug up. At a press conference that day he admitted that he had planted the stones and had faked most of his discoveries. With his head bowed in shame, he said: “I was tempted by the Devil.”
The Sokal affair was a hoax by Alan Sokal (a physicist) perpetrated on the postmodern cultural studies journal Social Text (published by Duke University). In 1996, he submitted a paper of nonsense camouflaged in jargon to see if the journal would “publish an article liberally salted with nonsense if (a) it sounded good and (b) it flattered the editors’ ideological preconceptions.”

The paper, “Transgressing the Boundaries: Towards a Transformative Hermeneutics of Quantum Gravity”, was published in “Science Wars” that year. On the day of publication, Sokal announced (in a different paper,) that the article was a hoax. He said that Social Text was “a pastiche of left-wing cant, fawning references, grandiose quotations, and outright nonsense”. Much heated debate followed, especially regarding academic ethics.
Another recent example of this same situation is the 2005 Rooter Paper; this was a paper randomly generated by a computer which was submitted – and consequently approved as legitimate – to a scientific conference.
Archaeoraptor in 1999 National Geographic described this creature as the "missing link" between dinosaurs and birds.Yeah, not so much. Turns out this "fossil" found in China was actually a forgery constructed from rearranged pieces of real fossils from different species.
The Nacirema were supposedly a tribe of people living in North America, as described by Horace Miner in his anthropological paper. The tribe Miner described had many odd rituals including "scraping and lacerating the surface of the face with a sharp instrument" and another ritual that "consists of inserting a small bundle of hog hairs into the mouth, along with certain magical powders, and then moving the bundle in a highly formalized series of gestures." It was actually a satire of everyday American life. "Nacirema" is "American" spelled backward and the amazing rituals were brushing one’s teeth and shaving.
So is it wise to place all my faith in scientist and published facts or is it better to access data and determine if the results is valid. I must question everything it is my nature some folks I guess prefer to trust anything that is published in journals and on the net.

On to Bryon’s article I am not qualified nor do I wish to critique your article but because I RESPECT YOUR KNOWLEDGE I will point out one instance of inconsistency.
TDS, not the ph, that shocks them [fish]. The effects of shock can be offset by slowing mixing the waters……….. TDS is unique to each aquarium. BY MIXING WATERS TO PREVENT TDS SHOCK WILL ALSO ALTER THE PH OF THE TWO WATERS since you connected ph to tds by way of general hardness. {providing alternative explanation for the lack of effect of ph shock instead of tds shock caused by osmotic pressure}.
You said “Never use bottled drinking water; this likely has more TDS than most tap water.” WHY????
Would you be surprised the definition of TDS your article provides is the same word for word definition as given by the EPA secondary water standards as aesthetic aspects. You don’t address why the same definition can provide two different interpretations of what exactly are TDS. Interesting speculation you provided about TDS.
pop

 

[1077]

I am reminded of the Locust's,cricket's I hear on warm summer evening's spent fishing along the riverbank.Although they have nothing of discernible importance to say,, they nonetheless continue with their chatter.
I suspect they enjoy hearing the sound they make.
I will stand by the knowledge I have gained from my expierience of nearly 40 yrs in this hobby, and hope that other's may take from it that which may prove of use.
For those who wish to find their own way,,, I bid them good luck.

 

[Byron]

TDS, not the ph, that shocks them [fish]. The effects of shock can be offset by slowing mixing the waters……….. TDS is unique to each aquarium. BY MIXING WATERS TO PREVENT TDS SHOCK WILL ALSO ALTER THE PH OF THE TWO WATERS since you connected ph to tds by way of general hardness. {providing alternative explanation for the lack of effect of ph shock instead of tds shock caused by osmotic pressure}.

What is your point? All sources will recommend mixing the waters to avoid shock; both TDS and pH will be adjusted by this. My point, or rather the point of the biologist providing this fact, is that the TDS is actually the more critical of the two. Just as GH is actually of more significance to soft water fish than pH when making these adjustments.

You said “Never use bottled drinking water; this likely has more TDS than most tap water.” WHY????

Bottled drinking water is not usually "pure" water such as RO. It contains minerals, depending where it came from. So it is adding these, which are part of TDS. Thus, it is no better than the tap.

 

[pop]

When mixing waters from two separate aquariums not only prevents possible TDS shock it also removes the probability of ph shock. This is not proof that ph shock doesn’t exist or is always a myth in all possible circumstances.

It appears that in TDS rich environments the buffering capacity of hard water chemistry creates a very stable state for ph and removes the potential for drastic shifts in ph. Showing sudden changes in TDS concentration and the associated effects of osmoregulation are responsible for the negative / harmful results for our water critters not changes in ph.
In TDS poor environments that lacks the buffering capacity of hard water chemistry are sudden changes in TDS concentration and the associated effects of osmoregulation the only factors responsible for the negative / harmful results for our water critters or can there be sudden changes in ph with out altering concentrations of TDS. Soft water chemistry might offer a contingency to the notion of TDS shock and the myth of ph shock when including aspects of carbon dioxide, oxygen into considerations (carbon dioxide and oxygen are gases and not TDS).

Contingency:
Consider planted aquarium with very soft water and décor of driftwood. As the plants consume carbon dioxide they release dissolved oxygen into the water column which causes the ph to rise.
We all have some form of algae in our aquariums and algae is a plant that consumes carbon dioxide from the water column and releasing more oxygen raising the ph again. If you have lights in operation for the plants the light raises the temperature of the water column raising the ph even more. In aquariums the ph will always become acidic the more efficient your filter is in nitrifying. Biologically oxidizing ammonia to nitrate the more hydrogen ions H+ will be produced, slowly reducing the buffering abilities of the water column. Now the buffering capacity of soft water is so reduced that the ph becomes very unstable with the continued production of oxygen increasing ph levels fluctuate then crashes.


When the ph crashes in soft water are the results the product of TDS shock or are there other factors in play. Would sudden falling ph along with declining carbon dioxide (I do not know if the respiration of the water critters off sets plant consumption of carbon dioxide) affect ammonia and the nitrogen cycle in the water column, are there other effects to the water chemistry that are not being considered.
Magnesium appears to be an important element in water chemistry. I have read that magnesium is needed for proper osmotic function in water critters and is necessary for calcium assimilation. Can magnesium become toxic with falling ph levels; are there other elements that change toxicity with ph changes?

Pop
You all can’t put this possum in a cage……………………