GH, DH, DKH, KH and ppm???

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bullyboy

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So ive just started testing my KH and GH with an API kit.

As far as i know the GH is water hardness and KH is co2 in the water?

Im trying to find all the peramiter preferences for my flora and fauna stock and future stock

Can some one clear this up?
 
kH is carbonate hardness or buffering capacity. This affects the pH of the water. Having a higher kH is typically good because that will prevent pH swings that could be deadly. You must lower the kH to lower the pH and it is difficult. gH or general hardness is the measure of water hardness. This is the amount of minerals in the water, these minerals are crucial to the fish's well being. They include minerals like magnesium and calcium (and other less important) Some fish prefer more mineral water while others prefer less though the soft water fish can survive in hard water. The gH of a tank will gradually raise over time but doing water changes helps keep it at a stable level. I don't suggest getting fish that have needs vastly different from your gh kh and ph because kh and ph are annoying to change.
 
kH is carbonate hardness or buffering capacity. This affects the pH of the water. Having a higher kH is typically good because that will prevent pH swings that could be deadly. You must lower the kH to lower the pH and it is difficult. gH or general hardness is the measure of water hardness. This is the amount of minerals in the water, these minerals are crucial to the fish's well being. They include minerals like magnesium and calcium (and other less important) Some fish prefer more mineral water while others prefer less though the soft water fish can survive in hard water. The gH of a tank will gradually raise over time but doing water changes helps keep it at a stable level. I don't suggest getting fish that have needs vastly different from your gh kh and ph because kh and ph are annoying to change.
Is KH also used to measure Co2 in the water ?
 
Is KH also used to measure Co2 in the water ?
There's a relationship between kH and pH. Here's a calculator:
http://aquariuminfo.org/co2calculator.html

People have strong feelings about the accuracy of THE CHART (duhn duhn duhnnnnn), but I use the formula as a guideline.
Any one know what DK and DKH are measures for?
Just curious if you've clicked through any of the links other people have posted. We don't post them because we don't know. At least I don't. I generally post links when someone else has a concise explanation for a complicated topic and I don't feel like plagiarizing.
 
These initials you posted look like one and the same thing to me it's just that there are a number of different units to express them.

GH is general hardness as mentioned above and KH is carbonate hardness as mentioned above. They can be abbreviated as such depending on the units of measure people are referring to. For example.

The D refers to 'German degree' and is one of the units we use to express hardness. PPM (parts per million) is another and degrees Clarke would be another. We usually tend to talk in dGH or dKH. 1 dH is defined as 10 milligrams of calcium oxide per litre of water. This is equivalent to 17.85 milligrams of calcium carbonate per litre of water, or 17.85 ppm. So times your dGH by 17.85 to get ppm.

The chart is 100% accurate. When we try to use it for our fish tanks it becomes inaccurate and relying on it as a method to calculate co2 in your tank as even a reference point will cause more problems than it will solve.

Hope this helps.
 
kH pH and co2 have a relationship but you can't use the kH test kit as the measure of co2, the measurement is of the kH
 
kH pH and co2 have a relationship but you can't use the kH test kit as the measure of co2, the measurement is of the kH


KH test kits measure total alkalinity. Although carbonates are a predominant player when determining total alkalinity there are also other ions that contribute.

Using the test kit you add an acid to the water in your vial until the alkalinity is consumed. The ph drop is indicated by the colour change which gives you a 'KH' value. Drop checker works the same way.

The fact that the KH test kit is incapable of measuring Carbonates directly is another unfortunate misconception within the hobby. This is why using total alkalinity readings measured with our kits then transferring the value over to a chart that assumes KH is due to 100% carbonates is flawed from the very beginning because we are not using the portion of total alkalinity (HCO3 and CO3) that shares a special relationship with co2 (H2CO3) and ph and as a result the data we are putting in is already corrupt.
 
So i have one for ya.... any way that you know of to keep the Ph down from the start up?

Check out my thread "new experimental tank"
Im trying to manipulate the kh from the get go so that once its cycled it will remain at or below 7.0, the point being that it will be a plant nursery mainly
 
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