Adding KH buffer to Soft Water Tank.

misha

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I have very soft water and for last couple of years was adding Seachem Alkali Buffer. I did it to prevent ph Fluctuation. Sometimes I observed algae here and there. Then I found that less KH buffer I add, less algae I get. Slowly I stopped adding KH buffer. KH of my city water is: 0.5, GH- 0.5. I still add Gh buffer Seachem Equilibrium to condition my tank to GH-3. My question to Tom: Why do we need to add KH? I did not find any stress in my fish by not adding KH buffer. My ph fluctuates from 6.4 at night(Co2 inj. OFF) to 5.8 when Co2 inj. is on. Additions of KH in my opinion causing KH fluctuation and algae.Tom I think this forum is awaiting for your new article.
 

Philosophos

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This is a topic we've come back to a few times (KH that is) there's no real benefit to buffering KH up unless you've got species that require it. The pH changing really doesn't matter, it's KH (alkalinity) instability that causes issues.
 
P

paludarium

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I just read in a new German aquarium plants book http://www.amazon.de/Pflanzenaquaristik-á-Kramer-Hans-Georg/dp/3897451905, the author Hans-Georg Kramer had an interesting point of view about KH. He pointed out that high KH or HCO3 levels might hinder iron uptakes of the plants either in roots zone or leaves, and the transport of iron within the plants, cause formation of FePO4 in the plants, and lastly disrupt NO3 uptakes. Therefore KH should not be kept too high, especially for the trouble plants. However the book also indicates that nitrate levels should keep low for some plants, especially when the KH is high.:confused: I am confused..... I only know that KH issue is related to CO2...:rolleyes:

Regards,
Erich
 

misha

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Tom needs to change old theories about adding baking soda or some kind of alkaline buffers. Fish is not affected by ph fluctuations if it caused by addition of CO2. The main fluctuation that really causing fish stress is unstable TDS ( which includes sudden changes in KH,Gh, NO3, PO4 etc...) and causing some kind of osmotic stress.
 

Philosophos

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Those ideas are changing; every time the issue comes up, one of us inevitably makes the statement that worrying about KH for the sake of pH stability isn't necessary. Tom's usually got a full workload when it comes to writing articles, doing hobby related experiments, and his real job.

Perhaps you can help. Do your own reading on the subject, learn how to show that increasing KH for the sake of stability isn't relevant through theory and experimentation, then write about it. I'm sure the post would be very welcome both here and on other forums.
 

Tom Barr

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paludarium;44290 said:
IHe pointed out that high KH or HCO3 levels might hinder iron uptakes of the plants either in roots zone or leaves, and the transport of iron within the plants, cause formation of FePO4 in the plants, and lastly disrupt NO3 uptakes. Therefore KH should not be kept too high, especially for the trouble plants. However the book also indicates that nitrate levels should keep low for some plants, especially when the KH is high.:confused: I am confused..... I only know that KH issue is related to CO2...:rolleyes:

Regards,
Erich

I think you'd do well to stick with what you know there, as it's right on target.
I do not dispute the observation that certain species do poorly in higher KH's.
No one does I think.

How the KH and CO2 are affected is a curious thing. HCO3 blocking CO2, or some effect there seems more likely.

Is the pH of your blood able to change because we put you in say Mono Lake, CA a with a pH of 10.1 or in Lake Palcid in Florida with a pH of 4.7?

Endogenous homoestatsis within the plant is a very very very different process than external environment. Plants, virtually all organisms would perish if they where subjected to those same conditions, even a bacterium does this.

They have to push against a concentrational gradient.
Plants do this with Salts all the time. They are also quite good at it. They have excellent "gate keeping" of various chemicals inside them, many of which if left alone and not controlled, would kill everything in the plant. This sounds more like poor Biological understanding on his part from what you have stated here.

NO3 has no impact on plants over a wide range other than generally more growth with increase in concentrations up to about 30-40ppm for aquatic species, in fact, 98% of aquatic plants grown commercially, including perhaps 100% of thr German supplies from growers, comes from Tropica which uses standard type of Hydroponics to grow plants, the average concentrations for most Hoagland modified solutions is 200-240ppm of NO3.

If you limit NO3, then you also limit all other down stream nutrients, and you can also have a case where strong NO3 limits CO2 demand, just like with PO4 if the limitation is stronger than the CO2 limitation.

Maybe it was CO2, not anything to do with NO3?
How did he know the CO2 was good or not? Unless you have a reference to compare to and a good stable tank, you cannot say, you can speculate, but you cannot say.

Even a person with no experience can reason that if you want to test and see if these claims are true, all you need to do is show a few cases where this occurs under high NO3 and high KH, and you can clearly see the hypothesis is not correct.

Some species of plants do poorly at high KH, I do not dispute that, but Fe can be added using DTPA and other chelators that are not hindered at higher pH/KH's, and the internal environment is not exposed either.

Also, if you plan on setting up any test, you MUST test all sides, not just the ones you happen to "believe". Again, common sense prevails here=>

For any nutrient test you must be able a non limiting reference, and a severely limiting reference, all other results will fall in between. I can tell real quick if someone has not done a non limiting reference;)

Why?
I've done many of them and with most every species I can get my grubbly little hands on.

Here's a high NO3(30ppm), high KH(11 degrees), high GH too(24 degrees), but CO2 rich and non limiting nutrients:

DSCN0195.jpg


55gal2resized.jpg


25galwithsurfaceripple.jpg


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I thinkj he might need to be a lot more specific and give specific ppm;'s, KH's and specific species that can or cannot be grown at high KH's say 5-7 degrees or higher.

Then even that is speculation, we ask around and see if anyone is growing say Tonina well at a higher KH than say 6-7 degrees and then compare. We must start with the observations and look at all sides, not just what we might want to believe or fall prey to repeating a good myth.

I know NO3 over a wide range has no direct impacts on plant health unless it gets too low, some species do much worse than others at lower ppm of NO3.
I know of no plant that does poorly at say 30ppm of NO3.

None.

So that issue can be ruled out pretty effectively.
Fe, I think that also can be dealt with.
CO2 and KH and the effects, that's tougher. But here's how you could answer part of the issue: grow the plants in high KH hydroponically, as the CO2 will be non limiting and KH of the the air....is well, not present.

If they still grow well at high KH tap water, well, then it's more likley, that it's a CO2 uptake issue.

You also need to have nutrients in the sediments and in the water and then just in either location. You can speculate, ask, pose the question has anyone been able to grow in these conditions this species well? Few do that however, they just think because they personally have some correlation, that is means that there is cause. It does not.

A good myth is hard to kill.

Regards,
Tom Barr
 

Tom Barr

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If you have noticed, I'm hesitant to write a book and to say what causes some things.

Why? Because I honestly do not know yet, and might never "know".
I know what things are not..........but why algae and why this or that, many specifics I do not know.

I'd be scared to write in a book anything of the sort, I do not read German, so I am only going off what you have said:cool:

Living in Santa Barbara CA with rock hard water, and in Davis which had some of the worst salt water tap(well, not that bad but not far off), I soon realized that hard water, at least GH was a good thing. For KH, that's another matter.

I had to cut the KH to 5 to get these plants to do well using RO:

resizedsideview20.jpg


At 18 KH they did poorly.

With good ADA AS, they did much better, as with delta clay sediments.
Still, it took 3x less KH.

As far as CO2, I tried a lot, but I cannot rule that out either as a potential issue.
As far as high Mg, I had really high Mg in Davis, 50-60ppm of Mg.
Even cut, this means about 15ppm or so at least, and more like, 20-30ppm over time since it far exceeds plant uptake/export.

So I can rule Mg excess as an issue, as well as high Ca(around 80-100ppm Ca in SB, CA).

That leaves me with KH. Perhaps the uptake of most all enzymes functions poorly at higher pH's, but pH alone is not it since we can knock the pH down easily with CO2...........

Rather, the KH itself causes the enzymes to function poorly through stronger buffering.

I do not know.
It does not block Fe however, we can add it, marine plants also have no issues with it either. DTPA and other chelators do well at higher KH's/pH's(assuming no CO2 enrichment) also for Fe dosing.

What specifically does Fe limitation look like in these so called high KH tanks?
I'm not sure many have seen that specific to each plant species and that one nutrient itself.

Lots of guessing and not much getting ruled out.
I see a lot of folks doing that, I think it's best to say what something is not to the best of our abilities first, then see what's left we can test. That narrows the field down and we get much farther alone with less wasted labor, time, $ etc.

Regards,
Tom Barr
 

Tom Barr

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misha;44282 said:
I have very soft water and for last couple of years was adding Seachem Alkali Buffer. I did it to prevent ph Fluctuation. Sometimes I observed algae here and there. Then I found that less KH buffer I add, less algae I get. Slowly I stopped adding KH buffer. KH of my city water is: 0.5, GH- 0.5. I still add Gh buffer Seachem Equilibrium to condition my tank to GH-3. My question to Tom: Why do we need to add KH? I did not find any stress in my fish by not adding KH buffer. My ph fluctuates from 6.4 at night(Co2 inj. OFF) to 5.8 when Co2 inj. is on. Additions of KH in my opinion causing KH fluctuation and algae.Tom I think this forum is awaiting for your new article.

Honestly, I do not think we do, as long as there is some KH.
I have 18-20ppm of KH, about 1 degree, a tad over.

I do not change or mess with the KH typically, unless I live in Davis(horrid very deep well salty tap water).

I'm not fond of using RO filters.
GH is a nutrient, so is CO2, so focus there.

I'd focus more on CO2 for the algae/sub optimal plant growth.
Reducing light => reduced CO2 demand=> reduced nutrient demand.

That typically fixes most issues along with very careful adjustments of CO2 and observation/tweaking.

I'd go that route.

Regards,
Tom Barr


Regards,
Tom Barr
 
P

paludarium

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Thanks for the reply, Tom. I also believe CO2 should be the main issue to focus on here. Recently I found the website of Dr. John E. Titus http://www2.binghamton.edu/biology/faculty/titus/publications.htm, there are many interesting researches related to CO2 and submersed macrophytes, but I can only read some of the abstracts/summaries. It seems that we do not have to worry about low pH, well, at least for the aquatic plants. http://www.springerlink.com/content/g368h131066n2678/, http://www.springerlink.com/content/hh87764l98664hr7/ and http://www.sciencedirect.com/scienc...=4607904&md5=cdbd9be35288057ff0705b39a8fd09c7.

Regards,
Erich
 

Tom Barr

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paludarium;44396 said:
Thanks for the reply, Tom. I also believe CO2 should be the main issue to focus on here. Recently I found the website of Dr. John E. Titus http://www2.binghamton.edu/biology/faculty/titus/publications.htm, there are many interesting researches related to CO2 and submersed macrophytes, but I can only read some of the abstracts/summaries. It seems that we do not have to worry about low pH, well, at least for the aquatic plants. http://www.springerlink.com/content/g368h131066n2678/, http://www.springerlink.com/content/hh87764l98664hr7/ and http://www.sciencedirect.com/scienc...=4607904&md5=cdbd9be35288057ff0705b39a8fd09c7.

Regards,
Erich

Yes, John Titus was very interested in CO2.

This was popular about 1970's through around 2000. Seems funding and interest waned after that.

Regards,
Tom Barr