Full control over parameters in aquarium water

Aquatest – tests for measuring water parameters

Aquatest GH-KH

Measurement of General
and Carbonate Hardness

Aquatest GH-KH is a set of two tests for measurement of general (GH) and carbonate (KH) hardness with an accuracy of 0,5-2 °d (Degrees of German Hardness) depending on a volume taken according to the instructions of use. The determination is simple and accurate. The reagent is added in drop form (every drop should be counted) to the measured water sample until the solution turns a colour matching one from the colour scale, which indicates the end of the reaction progress. The volume of reagents GH and KH permits to determine approximately 2×300°d.

Why measure water hardness?

The General Hardness of water is a measurement of multivalent metal cations, mainly cations of calcium and magnesium. This parameter has considerable influence on many life processes including cell membrane permeability, osmotic pressure, as well as biochemical transformations. Carbonate Hardness (alkalinity) is a measurement of the buffering capacity of water and will determine the stability of aquarium water pH. Generally contributing to alkalinity are calcium and magnesium bicarbonates but in some aqueous media, the presence of sodium and potassium bicarbonates also has the same effect.

How to correct water hardness?

Most aquarium fish require general hardness of water in the range of 5 – 15 °d and carbonate hardness of 5 – 12 °d. However, in case of some fish species, especially during breeding, considerably more narrow and specific range of water hardness is necessary to obtain. Reducing general hardness of aquarium water can be carried out using Aquafix GH flow bags. Aquafix KH or Filtrax KH are designed for reducing general and carbonate hardness. Additionally, the preparation Aquacid is useful to reduce carbonate hardness (20 ml of preparation reduces GH by 6°d in 100 litres of water).