Explain Kh

[PBirdsong]

Someone please explain to me Kh and how you test for it.

 

[FishLuva15]

Kh, i believe that is Carbonate Hardness although i am not a master at the chemicals


i want to know what Dh or whatever it is means Dg? i donno

 

[Jchillin]

Kh is the measure of carbonate of your water. This is a crucial part of determining your water's buffering capacity, which decides the ph of your water. Usually, a low kh will have a low ph.

 

[coyote1066]

Conversion

Along similar lines, how do you convert ppm to dGH or dKH. My test kit only gives ppm but most fish profiles are in degrees (?).

 

[Jchillin]

the (d) usually refers to the number of drops that you add to the test bottle. Each drop (degree) is equal to 17.9 ppm.

 

[coyote1066]

Hmmm

I see what your saying: ppm/17.9 = d

However, I'm using strips for these two tests...and only these two tests.

 

[TankGirl]

KH is alkalinity, or the buffering capacity of your water. The main reason aquarists test for this is to determine how stable pH will be in your tank.

Buffering capacity is an indication of a stable pH, in that a low (poor) buffering capacity means pH can drop drastically with the introduction of acidic compounds (fishy waste, decaying organics like driftwood, peat, etc.). We like to see greater buffering capacity, or higher KH, because that means it takes a whole lot more acid to bring down the pH, thus making pH a more stable value in your tank, which is a good thing for your fish, since any tank over time will become more acidic as fish waste collects in the nooks and crannies.

KH should not be confused with hardness of your water, which is GH or general hardness, and is a very different thing. It is simpler and more accurate to think of KH as akalinity or buffering capacity, and link it to pH stability.

 

[greenmaji]

ppm X .056= dKH, ppm X .058= gKH
dKH is german degrees of hardness
gKH is grams per gallon

They sell test kits for measuring carbonate hardness and ones for total hardness..
If im not mistaking if yours gives you ppm I think thats the total hardness test..
Is it the Aquarium Pharmaceuticals brand drip test?
HTH

 

[Heiko]

just out of interest, how can you higher the KH to make your pH more stable?

 

[TankGirl]

Baking soda can be used if you want to measure and calculate and keep close tabs on it with each water change, or what most people do is use crushed coral in the filter, calciferous rocks or substrate (like aragonite sand or crushed coral).

 

[coyote1066]

greenmagi and tank girl,

I ask more out of curiosity since I don't really need to tinker with either. However I did want to see where I stood in regards to new fish or comparing my tank to others.

The test strips are Jungle Laboratories 5-in-1. I don't rely on the Nitrate, Nitrite or pH portions since I use an Aquarium Pharmaceuticals master kit for those.

My current readings are:

KH: 120 ppm
GH: 75 ppm

would that be:

dKH: 6.72
dGH: 4.2

?

 

[greenmaji]

If you read he book the test comes with.. were I got the information I posted earlier.. It usually explains this to you relative to the type of test it is..
that looks like some soft water to me by the way.. you only have to worry about buffering the KH for keeping the PH stable if the KH of the tap water is under 3.

 

[coyote1066]

If it came with a book I would have read it. Lol.

It has the chart, instructions, etc. on a litle fold-out on the bottle. Pretty basic info. According to the included chart the GH is indeed soft and the KH is ideal. In fact my pH has been very stable. The water hardness is also good for what I'm doing...thankfully since I hate calcium deposits. I used to live in Phoenix where everthing turned white after exposure to water.

I appreciate the conversion formula since now I can determine where I am in relation to everyone else.