Buffering Is KH Necessary

Biollante

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Hi All,

A small dispute has erupted over carbonate hardness and weather it is necessary at all.:confused:

To avoid any further hijack of http://www.barrreport.com/showthread.php/6825-gH-very-low, I started this thread.

Our friend Jonny contends that carbonate hardness is unnecessary as long as carbon dioxide is not injected, no fluctuations in KH can occur, because the water Discus live in as well as other tropical waters have low carbonate hardness, http://www.versaquatics.com/testingthewater.htm. ;)

I on the other hand think there are a couple of small differences between our closed aquatic systems and the open tropical waters Discus and such reside. I would also note that because of the lack of carbonate hardness the pH in many of those waters is very low, in some cases below five.

One of the problems people used to have with raising Discus in the olden days was the requirement for stable, very soft, low ph water. The modern domesticated Discus is popular precisely because the modern Discus is not nearly so demanding.

Of my favorite sites that talk about buffering, perhaps my favorite, http://www.thekrib.com/Plants/CO2/, http://www.skepticalaquarist.com/docs/water/alkaline.shtml and http://www.skepticalaquarist.com/docs/water/watbas.shtml.
An oldie but goodie http://koiclubsandiego.org/library/alkalinity.php.
http://www.fishdoc.co.uk/water/hardness.htm

Buffering has been an interest of mine, cannot say I can explain it, but I have seen the effects.

Any serious thoughts, explanations I would appreciate.:cool:

Biollante
 

BigFlusher

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It would seem unwise to operate a tank with no buffering.

isn't one of the problems with distilled or dionized water that very small changes cause large swings?

Joe
 

jonny_ftm

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Hi,
I hate the term dispute, this is just a discussion and I don't mean to be rude with anyone. Excuse my english expressions if sometimes my comments seem too direct. I'm also open to change my mind about KH...

Anyway,

To answer BigFlusher, using distilled is a bad idea as it has a GH of 0 and especially a very low conductivity, it will kill every fish. A very low GH, below 1, is present in most amazonian rivers where live most of our fish. Asian waters are also very soft. So, it is not the low GH that necessarely kills the fish, but the conductivity of the water that can make osmotic pressure too high on fish. Many breeders successefully keep wild Discus in KH 0 and GH near 2 or lower. Many asian breeders have a great success with KH 0 and GH near 2-3 with the most sensitive critter: high grade CRS

I questionned my self about this KH when I started keeping high grade RCS. Having a low KH, even 0, will help keep these shrimps at a PH in the 6 range in a stable manner, without using any CO2 or active soil. This is because water will be closer to CO2-KH-PH table. When no CO2 is injected, CO2 in water is near or lower than 5ppm, it will be never higher.

Akadama soil, will drop the PH by dropping the KH near 0 for example. Yet, CRS breeders are having a great success with it, when they don't inject CO2 (most don't inject CO2 anyway, as breeding tanks are usually substrate only tanks with just some mosses).

Now, in our planted tanks needing CO2, if the KH was 0, the PH fluctuations when CO2 is injected during the day will be very extreme. Thus, injecting CO2 without KH, can be dangerus for fish. Same thing with active substrates that will drop the PH. If no KH is present, than these soils can drop the PH too low by releasing organic or other acids. This could cause a too low PH for some species, especially if under 5.

Also using clay based soils can drop the PH too low if KH is 0, but there will be no fluctuations of the PH if you don't alter things by injecting CO2

In a CO2 tank, having some KH is mandatory in my estimations to avoid killing fish with extreme PH limits. If you don't inject CO2, having a KH of 0 will be the easiest way to have a stable PH in the 6 and lower range, depending on type of substrate and roots you have in tanks. Your fish will be happier than ever with these stable conditions

When Tom is back, hopefully he can add some light on this
 

Tom Barr

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I think you make the mistake of assuming that pH is of importance.

CO2 is the same if you have KH oir it is near zero...........

CO2 kills the fish, not the salts or pH.

You have trouble measuring the CO2 at or near zero KH, but if you add say 17.86 ppm of KH to a system and then remove oit, with the same CO2 being added, the end should be the same, the CO2 should be the same as the gas is still being added at the same rate.

As far as more practical matters..........if.........pH change, dramatic or otherwise, caused issues for CRS's, Discus or any other species of interest, then when we do a large water change, say 80% and the pH changes over 1 full unit in less than 5 minutes, why do not the CRS or fish have any issues at all?
It's not the pH in other words, rather, the CO2 that is killing fish due to poor management and measure.

pH alone cannot account for this, even practical experience quickly reveals this result/fact.

So is it due to the pH change when the Kh drops?
Not that I can demonstrate using either discus or CRS's.

As far as non CO2 systems, yes, but you want low KH for CRS and Discus anyway, the Gh can be rather high without issues for both species.
So low KH is more an issue of measuring CO2 perhaps for many, there is some issue with KH and CO2 dissolving and balance, but it's rather minor in practical terms and in real aquariums where CO2(or not is added), the water change on a CO2 enriched system with RO or low KHJ water shows this when you measure the pH over the water change time frame.

I have a non CO2 ADA tank using large water changes with low KH/Gh tap. Plants and moss do well.
I think many have trouble going from CO2 to non CO2, they seem to think CO2 is mandatory.

It's not, but plants do grow much slower and things progress at a slow rate.
There's limited CO2, but not so bad once things adapt to it.

Some plants will use KH and knock the KH to near zero in non CO2 planted tanks, so KH becomes the carbon source if the CO2 goes low.
And without water changes, one of the tenants of the non CO2 methods, you quickly have a zero KH anyhow.

Regards,
Tom Barr
 

Biollante

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Buffering Is Irrelevent, I was Wrong

Hi Jonny, Tom, Joe, All

Well I learn something new every day, buffering is irrelevant, I am glad I asked the question. I am glad I got this answered it is an issue I see referred to quite a bit.

Jonny, I am sorry about my use of the word ‘dispute’, I think you and Joe (BigFlusher) were saying the same thing (the first post of isemino does say less than 1 dGH.

I guess this ‘buffering' issue is one I have had completely the wrong idea about. :eek:


Thanks,
Biollante
 

ismenio

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Hy everybody

Resuming
I have two tanks, one with 20 G with tropical fish and other with 100 G with goldfish.
The results was:
20 G - ph=6 and kH = 1º
100 G - ph=6 or bellow and kH =1º
Note that ph test is form API and the test was made before the light turn off and kH test is also from API but note at the frist drop turn water turn yellow and i don´t no really if it is 0 or 1 degree.

Then i have put Ca(HCO3)2 and rise the ph to 7,2 and today i have again test the ph and what i have found, in the 100 G with goldfish the ph is at 7 but the in the tabk with 20 G where the fish died from the night to day it has 6.4 !!!! why ????
In the two tanks i have now the kH at 2º

Why in the tank of 20 G the ph is getting low do fast? i have the same kh !!!

Regards
 

Biollante

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Apologies One And All

Hi ismenio,

I apologies for any advice I gave you.

Carbonate hardness and pH have no influence on fish or plants.

Before today, I would have been ready to talk about water parameters and small versus large volumes, nitric acid from humic or biological processes or whatever. I would have advised raising both GH and KH, especially for the Goldfish, after a major water change.

Now I realize how wrong I have been. I have not had time to process this information, which is frankly counter to pretty much everything I have ever thought I understood about water parameters. I cannot imagine our goldfish or African cichlids or a dozen others without some kind of pH stability.

I keep a range of plants and critters from what I thought to be a ridiculously low pH 4.8, some creepy crawlies at almost 9.

Once again my apologies.

Biollante
 

Tug

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i contributed to this mix-up and hope it never happens again; lets see if I have a better understanding. I'll be quick about it.

Now, I know that within reason, water with 2 dGH or higher is good (depending on what we are keeping)

Ranges of KH will depend on the source of water. It has a relationship with carbonic acid useful to CO2ers, but is otherwise benign - It is better to play the hand your dealt then to cheat.

KH can also drift up, thats bad (unless your adding CO2).

If you made it to here, some of the statements must be right. Right?

Just one more question, can we always detect KH (carbonate hardness) if we use buffering capacity testing?
 
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ismenio

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Hy
No one must ask for apologies, the suggestions that all of you gave was trying to help me.
But i think the kH is very important, i must maintain the tank with 100 Gallons at ph 7 or more not for the plants but for the fishes, Goldfish don´t like acid waters like ph at 6, if they can live don´t mean they like it, at this point i disagree form Tom Barr, sorry.

On the 20 Gallons tank i could get a middle solution like put the ph at 6.5 for example, but yesterday the ph was at 6.4 and today it is at 6.2

Now the question is: If the plants and fish don´t care with low kh or gh it´s fine but a fish that like a ph of 7,5 and after a few days it´s a 6 well i think that this don´t give good health, i sould have some kh or i will have ph going down.
One more question if i keep the ph at 6 when a make a water change i will produce a ph swing since the water that i use have ph of 7,5

Sorry this questions but i think they are important i think
 

Biollante

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Until Yesterday...

Hi,

Until yesterday I would have agreed with you. I have to say that I keep a lot of critters, some kind of exotic, quite a few plants, two or three worthy of interest and the concept that any critter or plant can survive and thrive in any pH is stunning to me.

I really have not processed this yet, but Tom Barr (and Jonny) were unequivocal, no room for discussions, no "ifs", "and" or "buts". I have like a thousand links to people that seem to think there is at least room for discussion, but for our purposes and understanding, they are all wrong or worse fraudsters and hucksters.

I also keep a large number of goldfish in heavily planted aquaria and have always believed they required buffering and that pH was important.

I have moved a few of the more common species to six new setups starting at the parameters and water quality I believed important and will let different conditions develop, mainly trying to avoid sudden drastic changes, though according to Tom Barr's missive that should not make any difference.

I have begun the same process with other plants and critters.

Biollante
 

BigFlusher

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i still think it is unwise to operate most (all?) tanks with no buffering.

i still contend one of the problems with distilled or dionized water that very small changes cause large swings?

if pH is not of any concern and will not harm any fish, why do i see such a slow down and die off of bacteria in filters when the pH drops below 5.0-2 or so.

everyone can tell me how stupid i am and maybe i am not all that bright, but given that fish are not the closed system mammals are, i simply cannot buy that fish are not harmed by ph ranging below 5 and down to 4.6, especially goldfish and livebearers ismenio.

ismenio: use the baking soda and bring the KH up to at least dKH 5, dKH 8 or 9 won't hurt. 6 grams baking soda for each 50 liters will raise the dKH 4, for the 20-gallon tank 2 grams for each 4 dKH you want. in your 100-gallon tank add 45 grams for each 4 dKH desired.

i don't care if i get barr'ed for disagreeing.

stupidly yours,
Joe

Joe
 

jonny_ftm

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Hi,

Baking soda in those ammounts is a bad idea, you add too much sodium.
Again, BigFlusher, using RO/distilled is bad because GH and conductivity are near 0, fish will explode their skin. It's not the PH.
Distilled has a PH around 6-6.5. If you put fish in it though, it won't live a long time because of the osmotic shok due to a conductivity near 0

I still have a question for Tom. If you use distilled where you add only GH, so KH of near 0 in a CO2 tank. By expierience, the PH can be in the 4 range with some soils or CO2. Don't you think that most species won't make it in the long term in such a PH? Having some KH in a CO2 tank looks wise, also in non CO2, depending on soil.
 

ismenio

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Has Tom Barr say the ph swing over waters changes do not kill fish like discus that are very sensitive and i can agree with that but i can not agree with maintain others species that like uppers ph like 7,5 or 8 on ph like 6 or bellow, how can i rise the ph without rise the kh?

Regards
 

ismenio

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To Tom Barr

By the way, let´s suppose for the next examples all are planted tanks

1º Scenario

Tank with the water source with PH at 7,5 ph and KH at 4º with no CO2 ,after a month the ph will maintain or drop? I think will drop

2º Scenario

Tank with the water source with PH at 7,5 ph and KH at 4º and with CO2 ,after a month the ph will maintain or drop? I think will maintain.

I think when we add CO2 to a tank we are helping to maintain the KH stable since the plants have a better source for CO2
Relative to ph it seems have a direct relation with KH; high ph equal to high kh.
And the table PH-KH-CO2 it seems to be wrong, with a ph of 6 with kh 1º i will have 30 ppm of CO2 that is false sinse i don´t inject CO2 in the tanks.

If i´m wrong please explain.

Regards
 

BigFlusher

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jonny_ftm;45495 said:
Hi,

Baking soda in those ammounts is a bad idea, you add too much sodium.
Again, BigFlusher, using RO/distilled is bad because GH and conductivity are near 0, fish will explode their skin. It's not the PH.
Distilled has a PH around 6-6.5. If you put fish in it though, it won't live a long time because of the osmotic shok due to a conductivity near 0

I still have a question for Tom. If you use distilled where you add only GH, so KH of near 0 in a CO2 tank. By expierience, the PH can be in the 4 range with some soils or CO2. Don't you think that most species won't make it in the long term in such a PH? Having some KH in a CO2 tank looks wise, also in non CO2, depending on soil.

I understand you guys know all... but i do not believe goldfish or live bearers are likely to be harmed as quickly by adding a small amount of salt than subjecting the goldfish to pH's in the 4's.

at some point a little common sense should prevail.

i see quite a number of very educated and competent people out there recommending buffering and some attention to pH. I cannot believe everyone of them is wrong, a fraud, or a liar.

If you don't like baking soda, use plaster of paris or quick-lime or something. Given the crisis situation that ismenio is in I would go with straight rock salt.

First the criticism is that the 'natural' aquarium will have too much salt if we use baking soda, then suddenly the 'proof' everyone in all forums, all literature are wrong is that water changes do not kill Discus. If we are doing weekly water changes what is the 'big' risk with baking soda?

I still do not see how, unless every chemist is a liar, that distilled water which the lying chemists claim, have an affinity for change, yes the pH may be 7, but it does not stay that way.

Distilled water is by itself dangerous, unless reconstituted and if that reconstitution does not include some carbonate hardness... then it will be greatly influenced by the products of biologic activity, the soils, by a number of sources.

i should not have answered. I will refrain. back to TPT.

stupidly yours,
Joe
 

Biollante

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Hi All,

I really fear that Joe may be right and ismenio is not being well served.

It is somewhat funny how the argument altered. Where the proof that water in a natural aquarium should not be buffered; is that Discus, do not die because of a water-change.

But the fact that the statement in post four is so absolute, so definitive, that given Tom Barr's reputation and professional standing, I think we have to accept that he is correct.

It is directly opposite my experience and every practice, but I am not a scientist and what I have attributed to lack of buffering or requirements of various species must be attributable to some variable I have not considered.

Biollante
 

Tom Barr

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BigFlusher;45492 said:
i still think it is unwise to operate most (all?) tanks with no buffering.

i still contend one of the problems with distilled or dionized water that very small changes cause large swings?

if pH is not of any concern and will not harm any fish, why do i see such a slow down and die off of bacteria in filters when the pH drops below 5.0-2 or so.

everyone can tell me how stupid i am and maybe i am not all that bright, but given that fish are not the closed system mammals are, i simply cannot buy that fish are not harmed by ph ranging below 5 and down to 4.6, especially goldfish and livebearers ismenio.

ismenio: use the baking soda and bring the KH up to at least dKH 5, dKH 8 or 9 won't hurt. 6 grams baking soda for each 50 liters will raise the dKH 4, for the 20-gallon tank 2 grams for each 4 dKH you want. in your 100-gallon tank add 45 grams for each 4 dKH desired.

i don't care if i get barr'ed for disagreeing.

stupidly yours,
Joe

Joe

Ya do not get barred for that, you get barred for being personal. Or spam. But only 3 have ever been barred............not a high count given the volume and google rating. Likely the lowest barred ratio of any web site I'd reckon.
As long as you can back it up, not treat what has been written by some hobbyists as generalized dogma.........as support.

Then it's game, even if you cannot do that, and just feel it's wrong, that's fine too, you can go figure out a way, or step to demostrate you are correct.

As far as KH/buffering, it's good to some extent for some species, others not much, and when adding CO2, it really does not apply much as far as pH, measurement perhaps........but not much else.
I have low KH, I really highly doubt anyone has true absolute zero 0.0000 KH.

There's bound to be a little in there.

Few have tap that is less than say 1 degree(17.86ppm).
For water treatment purposes, it would be very rare, but could be done with hyper purification and lots of frequent water changes.

So very few special cases.

For us and CO2?
Not much use.

For non CO2 planted?
Why bother?

pH moves a full 1-2, even 4 full units in tide pools(well about 2) in shallow planted lakes and ponds every day..........or few hours for tide pools.
This is a huge wide range of habitats for marine/FW systwems that change rapidly and hugely.

This occurs all over the place.

The same can and does occur in aquariums also without issue as far as plant effects on pH due to CO2 changes.

CO2 is not a salt, changing pH via baking soda however is and far more lethal.
Adding toxic levels of CO2 will kill the fish, but not due to pH.

Regards,
Tom Barr
 

ismenio

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Tom Barr;45522 said:
As far as KH/buffering, it's good to some extent for some species, others not much, and when adding CO2, it really does not apply much as far as pH, measurement perhaps........but not much else.
I have low KH, I really highly doubt anyone has true absolute zero 0.0000 KH.
Tom Barr
I agree , i have a low Kh near zero but isn´t zero.

Tom Barr;45522 said:
For non CO2 planted?
Why bother?
Tom Barr
I disagree, with EI applied to non CO2 tanks will generate some trouble with some species of fish, since the waters changes are made rarely the ph will go down and will not rise again.

Tom Barr;45522 said:
pH moves a full 1-2, even 4 full units in tide pools(well about 2) in shallow planted lakes and ponds every day..........or few hours for tide pools.
This is a huge wide range of habitats for marine/FW systwems that change rapidly and hugely.
Tom Barr
I agree the ph will always during the day go between 6 and 7 for example

Tom Barr;45522 said:
CO2 is not a salt, changing pH via baking soda however is and far more lethal.
Adding toxic levels of CO2 will kill the fish, but not due to pH.

Regards,
Tom Barr
Well, baking soda could be more lethal but what can i do?
 

jonny_ftm

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Hi ismenio,

If you really like to test increaing the KH, despite what you were told, you can add CaCO3 or MgCO3, far better than baking soda in my opinon.

About your KH/PH/CO2 table conclusions, we all know and claim that this table should never be used. It doesn't account for anything but KH and CO2 in the PH balance, which is wrong in our aquariums.

Unless you have a very low PH, 4-5, with fish originating from hard waters, I don't think you should be concerned. If you're concerned about fish health, focus on the GH/conductivity ranges to avoid extreme limits of the specie and perfect maintenance. Tanks with no water changes or few water changes, will never make fish live for its life expectency like with regular water changes
 

ismenio

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Thanks jonny_ftm

I will start with the waters changes all weeks to avoid the use of backing soda, i think it´s the best for my problems.

Thanks to all that help me.

PS: One day i will try maintain discus and angel fish in ph of 8 side by side with African Cichlid.