Test kit ZOOLEK TEST GH-KH for measuring general hardness (GH) and carbonate hardness (KH)

ZOOLEK TEST GH-KH is a chemical test kit for measuring general hardness (GH) and carbonate hardness (KH) in water. The kit is intended for routine checks of mineral content in aquarium and pond water as well as for monitoring water used in conditioning and treatment tasks. The test kit delivers colorimetric results that help evaluate calcium, magnesium and carbonate/bicarbonate levels affecting fish health, plant growth and buffer capacity.

Advantages

The kit offers a straightforward titration-based procedure with visual color change endpoints for both GH and KH parameters, enabling quick assessment without specialized instruments. Test reagents are formulated to provide clear, distinguishable results over typical freshwater hardness ranges. The compact kit design includes the necessary reagents and an instruction leaflet to perform repeated measurements at home or in small-scale professional settings.

Suitable for

• Freshwater aquariums and planted tanks monitoring
• Pond water quality checks for ornamental fish
• Pre-treatment and post-treatment checks in water conditioning
• Routine hobbyist and small laboratory hardness testing

Key specifications

• Measured parameters: general hardness (GH) and carbonate hardness (KH)
• Measurement method: colorimetric titration with visual endpoint
• Suitable water type: freshwater (aquarium and pond)
• Result format: discrete hardness values expressed in degrees or ppm equivalents (via color change steps)
• Package contents: reagents and instruction leaflet for multiple tests

How to use

Collect a sample of the water to be tested in a clean container or the supplied test vial. For each parameter follow the kit instructions: add the specified number of drops of reagent to the sample and perform titration until the color change endpoint is reached. Compare the color transition or count titration drops as directed to determine the GH and KH values. Rinse glassware and cap after use and store reagents in a cool, dark place according to the printed instructions.

Usage recommendations

Perform tests regularly to track gradual changes in hardness and buffer capacity; test after water changes, when adding new livestock or plants, and when adjusting water chemistry. Use fresh reagents and follow the temperature and sample handling guidelines in the instruction leaflet to ensure repeatable results.