# Hardness?



## JBouchard1087 (Aug 8, 2005)

How do you test your water for hardness. Is there a kit for this, I just bought a huge kit from API and has everything but hardness. What is the ideal hardness for water in a fish tank?


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## gotbags-10 (Oct 3, 2006)

They have either the 5 in one test strips that test the alkalinity(hardness) or you can get the liquid gh/kh kits which is really the way to go. Try to keep it around 100ppm or 6degrees wichever the kits tests for the piranhas.


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## taylorhedrich (Mar 2, 2005)

I agree, look for the liquid test version, as it will be much more accurate than a dip strip.


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## JBouchard1087 (Aug 8, 2005)

taylorhedrich said:


> I agree, look for the liquid test version, as it will be much more accurate than a dip strip.


Ok, thanks for the help


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## harrykaa (Jan 10, 2005)

You perhaps know that there are two hardness parameters different form each other:
1) so called permanent hardness (dGH), which cannot be removed by boiling. Only chemically by water softeners or reverse osmosis (RO) system;
2) so called temporary harness (alkalinity, buffer capacity, dKH), which can be removed by boiling.

Real hardness values of dGH 1 - 16 (18-150 ppm, mg/l) are commonly tolerated by fishes.

A good buffer capacity (KH) is generally within the margins of dKH 3-6 (50-100 ppm, mg/l). A higehr value will usually raise the pH up to pH 8 - 8.4.

Harry


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