Colombo GH Refill

The Colombo GH Test Kit contains all you need for testing the total hardness of ponds and freshwater aquariums. The Colombo GH Test Kit comes complete with test tube and liquid reagents to provide accurate results for 40 tests.

The GH is the so-called total hardness or in German Gesamtharte, abbreviated to GH. The GH is the total amount of dissolved minerals like calcium and magnesium; in practice about 90% of the GH is made up from calcium, the remaining 10% is magnesium. These minerals are important substances for fish health but also for a good growth of water plants. In case of an adequate GH, these minerals do not limit the plant growth and thus plants can grow optimal. Optimal plant growth is the natural way for blocking algae growth, and thus an optimal GH is also important for clear water and keeping away blanketweed. Thus, test the GH regularly and refresh 10% of the water weekly.

An optimal GH-value in fresh water aquariums and ponds is between 8 and 12°DH. When the GH is above 15°DH, the water is too hard and white deposits in the form of lime can occur. You can lower the GH by refreshing water; first check the GH and add Colombo Fish Protect to the fresh water. When the GH is lower than 8°DH, you can increase it with Colombo GH+.

Instructions For Use:
1. Take a water sample of 5ml.
2. Add 5 drops of GH-1-test fluid and mix; the sample should be dad red to purple.
3. Add 1 drop of GH-2-test fluid and mix each time. When the sample turns blue, the GH is lower than 1°DH.
4. Add GH-2-test fluid drop by drop and mix, until the sample tums blue.
5. The number of drops added to induce the colour change from dark red/purple to blue, is equal to GH-value in °DH, so 2 drops = 2°DH, 3 drops = 3°DH and so on.