Colombo GH Test

If you’re unsure about mineral levels in your pond, test GH. The Colombo GH Test measures general hardness – the level of dissolved minerals such as calcium and magnesium in your water.

GH plays a role in overall fish health and water balance. Too low or too high can affect stability, plant growth and how other parameters behave.

Why GH matters

• Supports healthy fish development
• Contributes to stable water chemistry
• Influences plant growth
• Works alongside KH to maintain balance

In koi ponds, understanding GH helps you build a complete picture of water quality rather than relying on pH alone.

What’s included

• Liquid drop test reagents
• Test tube
• Colour comparison chart
• Instructions

The clear colour change makes readings easy to interpret, whether you’re testing routinely or adjusting source water.

When to test GH

• At the start of the season
• After topping up with tap or borehole water
• When adjusting KH
• As part of regular monthly water checks

Good practice & safety

• Rinse test equipment with pond water before and after use.
• Store reagents cool and out of direct sunlight.
• Keep all chemicals out of reach of children and pets.