high kH and sensitive plants

Soggy

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ive been searching the net for information regarding this but i only end up with the idea that a high kH is bad for some sensitive plants. There is practically no info on low kH affecting plants.

My tap water has around 14 dkH and while most plants are growing like crazy, others simply melt (rotala "vietnam", "nanjean" & macandra red). Im dosing EI, drop checker is green, filters are clean, great water current etc.

Im thinking of getting some acid buffers to destroy kH but i thought id ask before i go that route.
 

ShaneSmith

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It is not that the plants are sensitive to KH, i am convinced of that. The problem is that the plants are incapable to take in micronutrients at higher pH's. So i think that seachem acid buffer would be a viable solution. RO is a very expensive solution to a simple problem, Horticulturalists in nurseries have been fixing this problem with acids for a long time.
 

JDowns

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If discussion micronutrients, are we discussing the solubility at a higher PH. This would lead a train of thought that just using a better chelator would solve the micronutrient problem.

Personally I don't know. But I would lean towards the plants ability of transports at higher osmotic pressures.

Would be an interesting discussion.
 

VaughnH

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I have never seen an experienced planted tank enthusiast recommending using an acid buffer, or any other acid to lower the pH or the KH. What is done with terrestrial plants, greenhouse plants, hydroponic plants has little relevance to how we can treat aquatic plants. The only effective way to lower the KH in our tanks is by adding RO/DI or distilled water.
 

captain_bu

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I agree with Hoppy. Tried the acid buffer route years ago and made a mess out of my water chemistry. It also gets expensive unless you rarely do water changes. I bought an RO unit but eventually stopped using it due to the amount of "waste" water generated. I live in California where water can be scarce and got sick of lugging buckets of "waste" water around the yard to water the garden with. I don't worry about my pH anymore. If you don't want to deal with RO water you could try using Aqua Soil as a substrate. After switching my substrate to Aqua Soil my KH went from 17 dKH out of the tap to 5 dKH in the tank, pH came down quite a bit too.
 

aquabillpers

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I wonder when we talk about "High KH" in this contest, if we aren't really talking about "High PH"?

The problem of nutrient absorption and nitrogen availability, among others, are directly related to high pH, not KH.

Bill
 

Tom Barr

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ShaneSmith;33171 said:
It is not that the plants are sensitive to KH, i am convinced of that. The problem is that the plants are incapable to take in micronutrients at higher pH's. So i think that seachem acid buffer would be a viable solution. RO is a very expensive solution to a simple problem, Horticulturalists in nurseries have been fixing this problem with acids for a long time.

They often use strong acids, like H2SO4,HCL, what do these do to KH?

Think about it.............

Seachem's acid buffer is neither of these and does nothing to KH(like any weak acid, it has no affect).

pH can easily be adjusted using CO2, but leaves KH alone indepodendently, yet folks still have issues with the plants at high KH's.

This clearly shows that KH, not pH in and of it's self is the issue. This is because CO2 can influence the pH very effectively while leaving the KH alone entirely.

So this test asks the right question about pH without any confounding issues with strong acids which destroy KH. You can soften the water's KH by adding HCL also, bit messy though.

Still convinced and sure?

See here then:
Hydroponics: A Practical Guide for ... - Google Book Search

Also, the graphs suggest they are less available etc, but not absent , there is no implied assumption that they are limiting, just not as available, nothing more. Folks often inject their own assumptions and are easily swayed/led astray. This is not a submersed situations where CO2 and KH play huge roles as well as leaf uptake.

Many of these nutrients are only needed in very small amounts, so the demand based on the rates of growth may not be limited at all, even though the relative availability based on pH in these graphs, which do not take into account KH, and CO2 enrichment is submersed conditions, is more specific and the real question being asked, not whether it's fine in horticulture nurseries, hydroponics etc.

RO is relatively cheap vs using SeaChem acid "buffer" which will not do anything here. It does not remove KH and will not help these plants.

This is old stuff, you can see discussions going way back on the APD about this stuff and the same assumptions etc.


Regards,
Tom Barr
 

ccLansman

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Just trying to make sense out of what you stated Tom. I as well have a KH of 15 or so, would my plant benefit from adding RO at water change time and lowering the KH?
 

Mooner

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I too have had no luck with Rotala Wallichi, and have tried multiple times. I can grow the heck out of other stems though. I also have hard water and use no RO. I currently have three small stems hanging on but doomed I'm sure. Just don't want to mess with RO for WC's on multiple tanks. I will just keep trying other/new plants to see what works in my water.
 

ShaneSmith

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Tom Barr;33191 said:
They often use strong acids, like H2SO4,HCL, what do these do to KH?

- Acid + Carbonate ---> Co2 + H2O.... Right?

Think about it.............

Seachem's acid buffer is neither of these and does nothing to KH(like any weak acid, it has no affect).

- It specifically says on the bottle it will lower carbonates by .8 milliequivalents per 1/4 tsp or something similar. How do you know its a weak acid? I have asked them what exactly the acid is and they refused to tell me.

pH can easily be adjusted using CO2, but leaves KH alone indepodendently, yet folks still have issues with the plants at high KH's.

-- If your water is high in KH, you might need more CO2 than is viable for the rest of the tanks health.

This clearly shows that KH, not pH in and of it's self is the issue. This is because CO2 can influence the pH very effectively while leaving the KH alone entirely.

-I am not sure if i get your point. At a pH between 5.5-6 i see micronutrients being highly available. Most people dont run enough co2 to drop their water down there. That i know of.

So this test asks the right question about pH without any confounding issues with strong acids which destroy KH. You can soften the water's KH by adding HCL also, bit messy though.

-- I see your point, but i know people who use phosphoric, citric, and lactic acid with good success...

Still convinced and sure?

See here then:
Hydroponics: A Practical Guide for ... - Google Book Search

Also, the graphs suggest they are less available etc, but not absent , there is no implied assumption that they are limiting, just not as available, nothing more. Folks often inject their own assumptions and are easily swayed/led astray. This is not a submersed situations where CO2 and KH play huge roles as well as leaf uptake.

-- I am familar with that graph, What i notice is a significant increase in the availability of micronutrients, and a decrease in macro nutrients and Ca Mg. I think the sweet spot for most people would be 6.0-6.5... Do you think that with co2 supplementation someone with a high KH will usually go that low? I know they are not completely unavailable but some species might not be able to take up ENOUGH to grow well (Right?)

Many of these nutrients are only needed in very small amounts, so the demand based on the rates of growth may not be limited at all, even though the relative availability based on pH in these graphs, which do not take into account KH, and CO2 enrichment is submersed conditions, is more specific and the real question being asked, not whether it's fine in horticulture nurseries, hydroponics etc.

-- I'm not sure i understand what your trying to say, is your pont that you think that KH reacts/affects the plants independent of pH? i'm confused


RO is relatively cheap vs using SeaChem acid "buffer" which will not do anything here. It does not remove KH and will not help these plants.
-- Maybe, i haven't sat down to figure that out. But those membranes are awfully epxnesive and the initial cost is very high as well

This is old stuff, you can see discussions going way back on the APD about this stuff and the same assumptions etc.

-- i still dont believe my assumptions are wrong, this information is coming from highly educated people

Let me know if i am totally off base here, my major is horticulture (UF like you) and i would like to learn as much as i can... but as far as i know this is what makes sense to me.


Regards,
Tom Barr

I hope my reply is not taken the wrong way, i recognize you are en expert.
 

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Mooner;33214 said:
I too have had no luck with Rotala Wallichi, and have tried multiple times. I can grow the heck out of other stems though. I also have hard water and use no RO. I currently have three small stems hanging on but doomed I'm sure. Just don't want to mess with RO for WC's on multiple tanks. I will just keep trying other/new plants to see what works in my water.

With lower KH's, about 5 or less, it grows like a weed though.
I have to prune it often.

You can keep the same CO2, light, other parameters and add more RO to see the effect. While the pH will go down overall whenever you reduce the KH, it's not enough to warrant any pH relatable issues, maybe .5 pH units in some cases, say 7 to 6.5, or 6.5 to 6 etc.



Regards,
Tom Barr
 

Tom Barr

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ShaneSmith;33228 said:
I hope my reply is not taken the wrong way, i recognize you are en expert.

No, I think folks take things the wrong way personally, it's not.
It's an open debate, folks are always welcomed to ask questions, support their views and look into the issue further, the goal is to learn more about it, not to be "right or wrong" for one's ego. We all seek the same thing, what is really going on and why, how etc.

So we all have the same goals.

You might refer to me as an expert, but I have not thought of myself this way at all, I'm wondering many things and have unanswered questions myself and need to be sure of what I think it going on, so I have to think of other ways to make sure I do not come to the wrong conclusion.

I have to confirm and test, look at the research and make sure it does indeed apply or not. Then ask others who have done the same etc.

I cannot just look and know:cool:
This way I can reason through it much easier, I might not know exact causes etc, but I can at least rule certain things out stepwise by tedsting what the most likely candidates are.

Then I'm left with only a few things/choice of what it might be, it might be 2 or more, it might be only one thing.
This way I can know what the differences are between pH, KH, nutrients in soil vs the water column, submersed sediments vs terrestrial etc.
You have to pick it apart to get at the root issue.

This has nothing to do with you personally, nor is in any way a negative critique towards you. It's the idea, not the person that's being debated.

When things turn personal, as they often do on the web, then you stop learning and just get pissed off. I could never do this for very long if that was my gig. In person, such debates come across very different, there's fast feedback and you can tell that the tone is very different than what you might assume on line text to be.

Instead, look for evidence to support your view, or learn more and change your view if you think the idea is valid etc. Convince yourself that it makes sense in other words. Heck, we all make bad assumptions and mistakes, that's how we learn actually. So we try and help others not repeat them and discuss the issues in depth. Everyone is the same here.

And do not be afraid to challenge anyone, as long as you have a good "on topic" leg stand upon. Many pull this baloney where they inject doubt into the debate and suggest impossible methods/test that no one will ever do just to corner the other guy, an example is intelligent Design Debates, and we have our share of folks that keep going on and on ad nauesum claiming say "NO3 at 20ppm causes algae:", then when that was disproven, they suggest this causes stress to fish, and then when that was shown to be false, they then go after shrimp............. and then when that was shown also to be false, they cook up some long term monkey business about health etc, but cannot ever test these issues themselves curiously, then they claim it's only he high grade Crystal Red shrimp that are having issues with high NO3...........well, now we have certainly narrowed it down to a few hundred folks keeping high grade CRS, not some generla baloney, even if we never answer their question.

We have to have some degree of reason to assume risk.

Others will try to attack the methods and claim it's not "research grade test", and keep carrying on and on about that part, but if you add something and it does not induce algae many times, it's a wide spread observation, we can repeat it, then that really does not matter. We can still see if adding PO4 causes algae or not or what occurs at higher KH's. We have a control tank to show that the system is independent and there is no affect on the fish, algae, plants etc.
All you need a re few folks with high KH's growing plants just fine at higher pH to disprove the hypothesis.

Then the other issues with the methods no longer matter, you KNOW the KH is high etc and that you have good growth, so with other tanks, then you know it must be another reason that the plants are not growing well, not pH/KH.
Folks have a bad time with growing plants for many many reasons, so we need to look at successes where they have FALSIFIED the hypothesis put forth.
If you think that something causes an affect, then we should be able to repeat it. If PO4 excess at 2ppm causes algae, then I should be able to see it and add PO4 to an otherwise algae free tank and get algae.

No need to do research and make a big deal out of it if the pilot study never shows much promise:)
You can read the hydroponic methods and other container nursery production water issues in a wide range of text if you are interested.
Then you gain from this and have a better understanding. Which is pretty much why we talk about this stuff!


Regards,
Tom Barr
 

Mooner

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Tom Barr;33234 said:
With lower KH's, about 5 or less, it grows like a weed though.
I have to prune it often.

You can keep the same CO2, light, other parameters and add more RO to see the effect. While the pH will go down overall whenever you reduce the KH, it's not enough to warrant any pH relatable issues, maybe .5 pH units in some cases, say 7 to 6.5, or 6.5 to 6 etc.



Regards,
Tom Barr

My KH is abut 5.6 - 6 out of the tap and tanks. Close to 5 but higher, maybe something else is going on? PH 8.12, GH 6.7, EC 303 and TDS 151 ppm. I do have luck with most plants but not others. I've been concentrating on CO2 a lot! Maybe someday I will try one tank for kicks wit RO to see what I can do.
 

Tom Barr

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Yes, try knocking the KH way down to 1 or so.
See the effect.

This should tell you. Once you get good growth, then slowly add the KH back via the tap. See if you get stunting. Repeat this a few times. Then you get a pretty good feel. But you need to have good growth to start with, otherwise you have no reference control to rule out CO2/light related issues as well as nutrient issues.

You must have a good control tank to test out against any issue, whether it's KH, PO4 causing algae or whatever.

If you have not yet mastered the control to produce such a tank consistently, then you are really not able to say much about the parameters and test whether or not it might be caused by something, you lack the control to do an independent test. Many folks that have trouble assume they do have such control and that they have reference situations in their tanks when they do not. You really don't and cannot make test worthy of conclusions without some control reference to go by.

It's a catch 22 for folks with problems, but many don't realize it.
I try and help, but some will not get it.

Others also tell them it's not this or that, but when you are that poor aquarist struggling, it's hard to believe at times.

I know.

I am not divorced from the raw reality that I have suffered along with many/most other aquarist. I recall it well.

Regards,
Tom Barr
 

Soggy

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Thanks for the input guys. I guess ill just leave my water as is. A pity though, that plants like these are rarely available in my country and when they do, they're still out of reach. :(

ccLansman;33276 said:
soo after all the above.... do plants tend to do better in a lower KH environemnt or could they care less?

some dont care. some react unfavorably. Its just hard to find a reliable list of plants that are sensitive since a lot of the stuff on the internet are based on experiences without thorough studies. But then the trends of people's experiences suggest that the plants listed on page 1 (the top few) are sensitive. We just need people to disprove it.

speaking of disproving, anyone able to grow Pogostemon stellata(Eusteralis stellata), UG and elatine tiandra in high kH (10 up) water? I was really really really fortunate to have some in my possession.
 

Tom Barr

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Soggy;33277 said:
We just need people to disprove it.

speaking of disproving, anyone able to grow Pogostemon stellata(Eusteralis stellata), UG and elatine tiandra in high kH (10 up) water? I was really really really fortunate to have some in my possession.

UG and Elatine, yes, up to a KH of about 6. I think there is a broader, but you have the right idea, you need to find folks that know they have high KH and are good at growing and able to grow the species.

Then you can test and possibly disprove what it is you suspect or not.
Simply because you cannot grow it, does not imply that it is impossible:D

Which is what many think.............

Regards,
Tom Barr