gH very low

ismenio

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Hy

I had the discus, post angels and at 28º now the temp is at 25º since the fishes like corys and mollys don´t need to be at 28º.
Regard that i have four angles in a tank at work with 15 neons for more them a year without any problem, and regard, only Java fern some gravel and no water changes cause my boss says that we do not need to change water, only add water to the top and the ph it is at 7, at this point i believe that plants heat kH like source of CO2.
Relativity to my tank with goldfish they wore to sicken with black spots over the heads and believe that i don´t have ammonia even nitrite at water, i have a huge filter 520 G/H full with 3.2 Kg of siporax, this burn are caused by low ph.
Believe the goldfish care with ph.

And now the GH test:
Tap water: 4º dH
20 G tank: 8º dH
90 G tank: 6º dH

I made the test to times and i don´t understand how the GH increase.

Biollante i thought we are free to talk !

Regards
 

jonny_ftm

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Hi ismenio,
First, forgive my english expressions for anything that can look to you as agressive or rude. I try my best to translate my mind from french...

I know it is hard to recognize sometimes, but most fish death, if not all, are caused by bad maintenance. Nitrite and ammonia spikes can't be necessarly detected, as Tom tought us.

A 20 gal tank is something small that not all fish will be happy in it. Again, loosing fish in groups/series often is due to ammonia/nitrite spikes. Diseases will affect fish easier in these conditions. Stressed fish die soon or later. Many people consider that if fish lived in specific conditions for one year then these conditions suite the fish. Discus for example should live up to 10 years or longer in an aquarium. So, if they live for 1 year before dying, people should consider rather that their life was shortened at 1/10 because of the bad maintenance.

I don't pretend to have the definite answer to your fish death, neither I'm accusing you for bad maintenance. But often, the most expierienced of us can sometimes be sure that his maintenance is perfect, yet, once deaths occur, after verifying 10 times all elements, something bad in the maintenance finally appears. PH and KH shouldn't be the culprit. You can solve them, but I'm sure, they won't solve the death issues in the long run
 

ismenio

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Thanks i have already give up from the idea put angels fish or discus but the tank has good maintenance and after that one corys and two mollys have died.
And forgive me but i don´t believe that a fish that live on the nature with a ph at 7,5 will like to be with a ph of 6.

Regards
 

jonny_ftm

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At a KH of 3-4, GH around 6-8, discus will live years and years + breeding at a PH of 7.5-8. Now, going extreme with PH around 4-5 is another story. Just don't push the limits and fish will be happy in clean water with a medium GH/KH values

http://www.ctdiscus.com/A_Basic_Guide_to_Discus.html

This man is breeding discus at PH 7.5-8 for example (I know many personally around me). In the link I pointed, keep in mind that many of his assumptions aren't necessarely true, especially PH fluctuations. Huge PH fluctuations are due to chemical molecules: CO2, organic and mineral acids, carbonate... If PH varries hugely in a short time, it means these chemicals varried too quickely in water ---> fish death caused by these chemicals, osmotic shok... not necessarely PH
 
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Biollante

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Hi Jonny,

I guess the point you make about domesticated Discus is pretty much the point I was making about the wild caught Discus.

Through whatever adaptive resource that creatures such as Discus have, over a short span of time, the Discus have adapted to the point where they not only survive, but thrive in water with parameters for removed from their South American home.

I suspect an argument can be made that just because a Discus can live in pH 8.0 water, weather the creatures might do better in water closer to the acidic side. I however will leave that debate to those who seriously raise and breed Discus. My Discus seem to live and breed well in pH 6.6 water, which not many years ago would have also been unthinkably high.

You make the point yourself that whatever caused the “swing,” there is not a magic ingredient called pH; some combination of conditions combine to create the conditions that we measure as pH.

We can play silly semantic games as to weather a “pH crash,” or “failure to buffer” or with our newfound instruments maybe a “conductivity crisis,” is at fault.

Precisely, Jonny I agree with you “just do not push the limits.”

I will continue my experiment, put I think Tom Barr may be wrong :eek: on this one, even with plants and keeping all else stable in two of the tanks I am already getting copepod and shrimp deaths and I am going to presume the bacteria population is taking a real hit. All of this in my experience and understanding will accelerate the “ph crash” or “failure to buffer” or “conductivity crisis.” For my purposes, I will yet think of it in terms of pH, antiquated as that might be, young sophisticates as Tom Barr may wish to coin a new term.

For those who believe, no proof is necessary. For those who don't believe, no proof is possible. -Stuart Chase

Biollante
 
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jonny_ftm

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Yes Biollante,

It is hard to isolate PH alone as a culprit as it depends directly on other chemicals in water. Varrying PH would always involve varrying a causing chemical (CO2, carbonate hardness, other organic/mineral acids...)

Keep in mind also that CO2 injected in tank will have 3 ways:
- a part is fixed and metabolised by plants
- a part will degas in atmosphere
- a part will lower PH by this reaction: CO2 + H2O H2CO3

Following quoted part must be skipped for chemistry allergics:

H2CO3 is a weak acid that can give H+ ions (H2CO3 H+ + HCO3-). H+ ions released are the reason of PH drop.

Now, H2CO3 can revert back to CO2 and degas once we stop CO2 injection. But, a part of it can react with CaSO4 in this manner:
H2CO3 + CaSO4
 

Biollante

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Hi Jonny,

I fully and completely agree, in and of itself, pH means little, a tip o’ the hat to Tom Barr. :)

However, pH is rather like blood pressure in you humans, it is a good quick indicator but it does not tell us exactly what is wrong. The blood pressure in one patient may alarm the medical folk while meaning nothing in another patient.

However, if the blood pressure is too high or too low the medical folk must act even though the causes are not understood. Though being honest (and to contort the analogy further) like blood pressure extremes most of time medical folks have a good idea the cause by observing the patient.

Likewise, if the pH suddenly drops, we can make some guesses, but sudden, or out of the ordinary drops in pH, with all due respect to Tom Barr, are or can be significant.

When I find water in a tank containing livebearers,and I expect to find a pH of 7.5, instead I find a pH of 4.9, I know something is wrong, if I am there in person it is probable that I will have seen and smelled the problem before I did the pH test.

I contend that without regard to the cause, I must stop any further drop in pH, baking soda may not be optimum, but it is available almost anywhere in the world. I may have to deal with sodium and stress issues, but if I was quick, enough most of the fish are still alive and most are likely to survive.

In addition to your “must be skipped for chemistry allergics:” I would have you add the reactions that produce weak nitric acids, the carbonic acid we have presumably taken into account and really should only produce a one degree drop.

In addressing our friend, ismenio, you correctly, asserted that tracking and being sure of exact cause of fish deaths is almost impossible given among other things, spurious or transient spikes in ammonia (forgive me for not directly quoting you, I am doing this from memory).

I agree that is why in my humble (I am a potted plant after all) opinion the unexpected drop in pH can be an indicator of among other things ammonia spikes.

As I track my experimental tanks through a “ph crash” induced principally through use of un-buffered distilled water while using enriched soil I am watching (and wincing) the cascade effect of which the pH is not the actor, but the lagging indicator in this little death spiral. :( These days I have the test equipment to observe and document much of it in real time. I confess the speed of it caught me of guard.

Biollante
 
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jonny_ftm

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In low PH waters (4 and lower), I read often that quiet no fish or plants live. But never tried it indeed
 

Biollante

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Hi Jonny,

This is what I mean at some point the pH, regardless the causes become the problem.

I keep some wild caught Discus, they seem to prefer ~ pH 4.8, though they look their best at ~ pH 5.5. Maintaining water quality in pH 4.8 with large messy carnivores is a genuine pain, since among others nitrosifyers and the nitrifying bacteria do not survive very well down in the 4's.

Biollante
 

jonny_ftm

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Again, the PH in its self maybe is not the culprit

PH is only H+ ions floating in water. A PH of 4 means so much acids are in the water (organic acids in the wild, without KH). It could also be those acids causing the problem. Now, a too acidic or basic solution will clearly cause irritation of the skin and mucosa. Just imagine putting a fish in sulfuric acid solution...

I think that out of extremes, PH will only be the reflector of other water quality parameters that could be most important for the fish
 

ismenio

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Hy :)
a month ago i have buy a ph meter form Hanna, after use the buffers of 4 and 7 to calibrate look what i found !

20 G tank: pH 4,7
90 G tank: pH 4,1

I have insert coralline sand on the filters and rize the ph to 7,5 at 8 and the dead have stopped.

My conclusion: Probably the ph don´t affect the fishes but will break the bacterias from cycle.

Regards
 

jonny_ftm

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ismenio;49255 said:
a month ago i have buy a ph meter form Hanna, after use the buffers of 4 and 7 to calibrate look what i found !
20 G tank: pH 4,7 - 90 G tank: pH 4,1
....
My conclusion: Probably the ph don´t affect the fishes but will break the bacterias from cycle.
I'm sorry to say it, but this is again a binary too simple assumption without any evidence based proof.

How can you be sure that nothing else but PH changed? Waterchange, feeding, CO2, light, nutrients, less fish load after your deaths, time passed, plants biomass, decaying leaves, a fish dead body hidden that finished its decaying...

So many things can modify more important factors than PH

As of the evidence based facts, here's just one article from the tons you can find about nitrification in low PH if you google it:


High-Rate Nitrification at Low pH in Suspended- and Attached-Biomass Reactors
Sheldon Tarre and Michal Green* - Faculty of Civil and Environmental Engineering, Technion, Haifa, Israel - Received 11 May 2004/ Accepted 4 July 2004

This article reports on high-rate nitrification at low pH in biofilm and suspended-biomass reactors by known chemolithotrophic bacteria. In the biofilm reactor, at low pH (4.3 ± 0.1) and low bulk ammonium concentrations (9.3 ± 3.3 mg · liter–1), a very high nitrification rate of 5.6 g of N oxidized · liter–1 · day–1 was achieved. The specific nitrification rate (0.55 g of N · g of biomass–1 · day–1) was similar to values reported for nitrifying reactors at optimal pH. In the suspended-biomass reactor, the average pH was significantly lower than that in the biofilm reactor (pH 3.8 ± 0.3), and values as low as pH 3.2 were found. In addition, measurements in the suspended-biomass reactor, using isotope-labeled ammonium (15N), showed that in spite of the very low pH, biomass growth occurred with a yield of 0.1 g of biomass · g of N oxidized–1. Fluorescence in situ hybridization using existing rRNA-targeted oligonucleotide probes showed that the nitrifying bacteria were from the monophyletic genus Nitrosomonas, suggesting that autotrophic nitrification at low pH is more widespread than previously thought. The results presented in this paper clearly show that autotrophic nitrifying bacteria have the ability to nitrify at a high rate at low pH and in the presence of only a negligible free ammonia concentration, suggesting the presence of an efficient ammonium uptake system and the means to cope with low pH.

Nitrifying bacteria are elemental organisms that existed before most other forms of life, they started the life. They survived to most extreme conditions, not just a PH of 4. There are few old papers talking about nitrification stopping below PH 6, but many other reports showed the opposite.

Tank in my signature have a KH around 1, CO2 on yellowish tint, PH measured between 5-6. I don't see algae or death there
 
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ismenio

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Well, my conclusion could be wrong i now that, bu the water changes are the same, feeding the same amount from the same mark, CO2 only excel, light is the same, nutrients are the same, more fish load cause a have more new born mollys at two lda 116 ancistrus, plants biomass the same, no decaying leaves a sure you , a fish dead body is most difficult to assume that i don´t have but if one dead fish could make some trouble, well...you now what i mean :)

It should be something else.

Regards
 

jonny_ftm

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I have to admit also a PH of 4 is rather low for life. Your PH was rather very low even for my taste :)
Could be nothing to do with bacteria, but fish could not like it very much

Let us know if problems come back or new conclusions. Always interesting to get others experiences. Thanks for the feedback