Hard, Soft Or Medium.

[shaunjdodge]

Hi, I am being possibly quite silly. But based on this pic what hardness is my water? "Clark, French and German". I thought I lived in England

Sorry to ask but I don't know what relates to what on here, all I want to know is the hardness of the water I'm putting into my aquarium.

Thanks.

 

[TwoTankAmin]

There is no picture.
 
Hardenss can be measured on a variety of scales. But in the hobby either ppm or German degrees are commonly used. Mist test kits employ the drops method. Each drop added in order to make the test solution change color = 1 odH. Add 3 drops and its 3 odH etc.
 

 
Water hardness follows the following guidelines. The unit dH means ``degree hardness'', while ppm means ``parts per million'', which is roughly equivalent to mg/L in water. 1 unit dH equals 17.8 ppm CaCO3. Most test kits give the hardness in units of CaCO3; this means the hardness is equivalent to that much CaCO3 in water but does not mean it actually came from CaCO3.

General Hardness

0 - 4 dH, 0 - 70 ppm : very soft
4 - 8 dH, 70 - 140 ppm : soft
8 - 12 dH, 140 - 210 ppm : medium hard
12 - 18 dH, 210 - 320 ppm : fairly hard
18 - 30 dH, 320 - 530 ppm : hard
higher : liquid rock

from http/fins.actwin.com/aquariafaq.html
 
or
 

 
Water hardness is often not expressed as a molar concentration, but rather in various units, such as degrees of general hardness (dGH), German degrees (°dH), parts per million (ppm, mg/L, or American degrees), grains per gallon (gpg), English degrees (°e, e, or °Clark), or French degrees (°fH, °F or °F; lowercase f is used to prevent confusion with degrees Fahrenheit). The table below shows conversion factors between the various units.

Hardness unit conversion.

 

mmol/L

ppm, mg/L

dGH, °dH

gpg

°e, °Clark

°fH

mmol/L

1

0.009991

0.1783

0.171

0.1424

0.09991

ppm, mg/L

100.1

1

17.85

17.12

14.25

10

dGH, °dH

5.608

0.05603

1

0.9591

0.7986

0.5603

gpg

5.847

0.05842

1.043

1

0.8327

0.5842

°e, °Clark

7.022

0.07016

1.252

1.201

1

0.7016

°fH

10.01

0.1

1.785

1.712

1.425

1

For example: 1 mmol/L = 100.1 ppm and 1 ppm = 0.056 dGH.

from http/en.wikipedia.org/wiki/Hard_water

 

[shaunjdodge]

Ok brilliant. As it stands I don't have a test kit only strips. This is my first investment end of this month

My local water is 7.04 German hardness. This I'm guessing would roughly make the water hardness 7.04?

Thank you.

 

[TwoTankAmin]

Yes 7.04 degrees which would be 126 ppm.
 
What makes this more confusing is that fact that neither GH nor KH tell the whole story. When working with water. the first step is to understand that pure water is a poor conductor of electricity. What makes it a good conductor are all the solids typically in it. These can be the components of GH and KH. But it doesn't stop there. All minerals, organics, ions etc. all contribute to the its ability to conduct electricity.
 
The upshot of this is  when one examines water for the variety of total solids dissolved in it, they do so by testing its conductivity. The more solids there are, the better conductor the water becomes. Not supprisingly the tool we use to measure this is called a conductivity meter and it reads in micro Siemens. But most of us are familiar with an alternative method or readings called TDS, or Total Dissolved Solids.
 
Some fish keepers who need to monitor conductivity/TDS will use a TDS meter which gives results in PPM.
 
If you want a more involved explanation of all of this you can have a quick read here http/www.mbhes.com/conductivity_measurement.htm