Ph, Gh and Kh for beginners. Have I got this right?

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I need to read Aquachem's response more carefully to make sure I understand :)

In the meantime, something occurred to me. Is it possible that terms like KH and GH might mean different things depending on the context? In other words, there might be the true, formal meaning in chemistry, and the casual, good-enough meaning for aquarium purposes?

For example, in general terms, GH might mean a range of minerals, but when people refer to GH in a conversation about aquariums, they mean the amount of magnesium and calcium specifically, because those are the things the aquarium tests measure?

Is that possible?
 
Just read all Marsha, this will be great to refer back to, I have a slight headache now...........will it be a sticky,?
 
When I say GH I mean minerals in general but I could be using it incorrectly.

The right verbage is probably that you want your GH test to register --- and to do that you can have more or less ---.

In troubleshooting GH and KH in my extremely soft water, I was reading that I could just use Epsom salts, baking soda, and ice melt stuff. But then I saw Seachem Equilibrium raises GH and has lots of other macros. I presumed that GH measures more than calcium and magnesium, due to that, but I guess it's more like "once you use enough to get your GH to 4, you also get all these extra micros."


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In troubleshooting GH and KH in my extremely soft water, I was reading that I could just use Epsom salts, baking soda, and ice melt stuff.
I have always been a little hesitant to add epsom salts to raise GH. It will definitely work, but do fish really need a large amount of magnesium in the water? I honestly don't know.

On the other hand, using baking soda to raise KH and pH is a pretty reasonable solution if you are targeting a pH of 8+.

Which ice melt product are people using?
 
I have always been a little hesitant to add epsom salts to raise GH. It will definitely work, but do fish really need a large amount of magnesium in the water? I honestly don't know.

On the other hand, using baking soda to raise KH and pH is a pretty reasonable solution if you are targeting a pH of 8+.

Which ice melt product are people using?


I just tried to find it in Diana Walstad's book Ecology of the Planted Aquarium, but can't. I think there are recipes online under DIY Ciclid Salts. I use API Chiclid Buffer and Seachem equilibrium because it seems better to get the traces ... But Cichlid Buffer plus Cichlid Salts works too. I read the suggestion to use "Chiclid" products in a community tank, when tapwater is really soft, in my favorite intro to aquariums book.

Here's an interesting quote from Diana Walstad's book: "“I would caution hobbyists to use water hardness whenever possible to classify their tapwater. It is the water hardness, not the pH or the alkalinity that counts. Although all three parameters are often correlated in nature, under artificial tapwater conditions they may not be. For example, some hobbyists report that their city tapwater has a very high pH and alkalinity, but has little hardness. This is because municipal treatment plants may add bicarbonates to acidic softwater to prevent corrosion of metal pipes. This water with its artificial alkalinity is still ‘softwater’ and, therefore, deficient in many hardwater plant nutrients (e.g., Ca, Mg, K, and S).”

Excerpt From: Diana Louise Walstad. “Ecology of the Planted Aquarium.” Echinodorus. iBooks.
This material may be protected by copyright.

Check out this book on the iBooks Store: https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=661029773

That speaks more to plants but I still contend fish need the minerals too.

Magnesium is critical for muscle and nerve function.


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Here it is ...

“Increasing water hardness from scratch is complicated. I would start with calcium chloride (CaCl2), which is sold as a winter “de-icer”. It dissolves quickly, doesn’t contain sulfates, and won’t increase the pH. A level tablespoon dissolved in one cup water is a reasonable working Ca solution. This Ca solution diluted 1:500 in distilled water gave me a GH of 4. One tsp (teaspoon) added to one gal is about a 1:800 dilution, so I would add a tsp of the Ca solution to each gal of tank water and measure the resulting GH. A reasonable scenario: the tank’s starting GH is 1 or 2, and you boost the GH to 4 or 7 with the Ca solution.
For magnesium, you can use Epsom’s salts, which is MgSO4. A level tsp of Epsom’s salts in 2 cups water is a reasonable working solution. This Mg solution when diluted 1:500 in distilled water gave me a GH of 1 to 2. A reasonable scenario: the tank’s starting GH is about 5 (after the CaCl2 addition) and you boost the GH to 6 or 7 with the Mg solution. I would add just enough of the Mg solution[…]”

Excerpt From: Diana Louise Walstad. “Ecology of the Planted Aquarium.” Echinodorus. iBooks.
This material may be protected by copyright.

Check out this book on the iBooks Store: https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=661029773

And a bunch that are cichlid specific ... https://www.google.com/search?q=diy+cichlid+salts&ie=UTF-8&oe=UTF-8&hl=en&client=safari

And this website has a lot of claims about GH, KH, and pH ... But it's selling a product and his "references" are more of his own articles. So I'd use it more as a jumping off point for better research.


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I need to read Aquachem's response more carefully to make sure I understand :)

Yes, the mathematics are pretty hairy, but it's a good concept to thoroughly understand. The law the governs pH/KH here is the same as what you use to calculate relative amounts of NH4+/NH3 to determine ammonia toxicity. In that case, NH4+/NH3 is the buffer rather than HCO3-/H2CO3.
 
Yes, the mathematics are pretty hairy, but it's a good concept to thoroughly understand. The law the governs pH/KH here is the same as what you use to calculate relative amounts of NH4+/NH3 to determine ammonia toxicity. In that case, NH4+/NH3 is the buffer rather than HCO3-/H2CO3.


The tough question is at what level of detail this needs to be understood, to keep healthy fish and advise others on doing the same?

I think it's sufficient to understand that KH isn't something you put in the water to make pH go up, it's something that helps hold pH at a certain level.



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The tough question is at what level of detail this needs to be understood, to keep healthy fish and advise others on doing the same?

I think it's sufficient to understand that KH isn't something you put in the water to make pH go up, it's something that helps hold pH at a certain level.

It would probably be enough to answer 90% of question, but it's that other 10% of questions that need that extra expertise.
 
The tough question is at what level of detail this needs to be understood, to keep healthy fish and advise others on doing the same?

I think it's sufficient to understand that KH isn't something you put in the water to make pH go up, it's something that helps hold pH at a certain level.



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Yes that's exactly what I'm trying to wrap my mind around.

The purpose of the article for me is not so much to understand KH in general, but to give people enough information so they can understand how it applies to aquarium keeping. Problem is I'm not experienced enough myself to know all the ins and outs of what might happen, what one might need to know.
 
I think it's sufficient to understand that KH isn't something you put in the water to make pH go up, it's something that helps hold pH at a certain level.
I agree that this is the most important part. The additional thing that I would add which is fairly simple to understand is that you cannot have a very high KH and a very low pH.

I see people trying to achieve this and causing endless pH swings by dosing with opposing additives.
 
Would it be accurate (if incomplete) to say, KH is what prevents pH from dropping?

I'm just thinking ... What's the fewest number of words that explains it sufficiently for 90% of fish keepers.

But I've only had to learn this for the purpose of preventing my 7.0 tap water from turning acidic overnight because Portland water is a little too fresh from the clouds. I'd presume, if I started keeping cichlids, I'd have to learn other stuff about KH and pH (and how to consistently and correctly spell cichlid).

"KH causes pH" would lead me to think "if I kept cichlids I'd just raise the KH more and my 7.0 tapwater will become 8.2" ... But that's the common false assumption isn't it?

Saying KH influences pH ... People with RODI or very soft water would have to add something that directly raises pH, and then increase KH enough to keep it there right?

I use premixed cichlid products to raise KH, and they do raise pH, but I'm pretty sure that's because something in the product is there specifically for pH.

But then again ... In my fishless cycle I used baking soda because I wanted a higher pH. It worked very briefly. The chichlid product kept the pH stably high until the cycle was finished.

I've just completely confused myself.

Part of the problem here is, in order to break it down into lay terms, one has to understand a lot more than needs to be conveyed. Lol.



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