NT Labs GH KH Hardness Test Kit

NT Labs GH KH Hardness Test Kit

The NT Labs GH KH Hardness Test Kit is a freshwater test kit for measuring GH and KH in ponds and aquariums. It suits pond keepers and fishkeepers who want a simple way to keep an eye on water hardness and buffering capacity, and it gives up to 80 tests from a single kit.

Key Benefits

• Measures both GH (general hardness) and KH (carbonate hardness) in one kit
• Suitable for freshwater ponds and freshwater aquariums
• Easy to use, with fast and accurate results
• Liquid reagents
• Gives up to 80 tests, so you can check your water regularly
• Comes with the test tube and liquid reagents you need to get started

What Is KH?
KH is also known as "total alkalinity" or "carbonate hardness". It measures the buffering capacity of your pond or aquarium water, which is how well the water can resist changes in pH.

What Is the Correct KH Level?
This kit measures KH in dKH, where one dKH = 17.8 ppm as CaCO3. Keep KH at a minimum of 4 dKH at all times. A KH of between 6 and 8 dKH is more desirable.

What to Do If KH Is Wrong

• Start by checking the KH of your tap water.
• If your tap water is above 6 dKH, regular water changes should keep the KH in the pond topped up at a reasonable level.
• If your tap water is below 6 dKH, you will need to add a KH buffer. Use NT Labs KH Buffer Up in a pond, or NT Labs Aquarium KH Up - PH Stabiliser in an aquarium.

What Is GH?
General hardness (GH) measures the total amount of minerals dissolved in the water. Water sits on a spectrum from "soft" to "hard", and the more minerals present, the greater the hardness. Hard water is also responsible for limescale build-up.

What Is the Correct GH Level?
This kit measures GH in dGH, where one degree = 17.8 ppm as CaCO3.

• Pond fish: 8 to 12 dGH is ideal
• Aquarium fish: the correct GH depends on the type of fish being kept
• Soft water species: aim for a GH of around 3 to 6 dGH
• Hard water species: 10 to 15 dGH is the correct range

What to Do If GH Is Wrong

• Test the GH of your tap water. It depends on whether you live in a hard or soft water area.
• If the water is too hard for the fish you keep, use an alternative water such as reverse osmosis water to lower the GH.
• In ponds, rainwater tends to lower the GH over time. NT Labs GH Minerals Up can be used to boost it back to a suitable level.
• In an aquarium, calcium carbonate rocks (like ocean rock) provide a continual source of GH minerals and can be used to increase GH.

Suitable For

• Freshwater aquariums
• Garden ponds
• Soft water and hard water aquarium species, where you need to match GH to the fish being kept

Specifications

• Tests: GH and KH
• Test type: liquid reagents
• Units: dGH and dKH (1 degree = 17.8 ppm as CaCO3)
• Number of tests: up to 80
• Water type: freshwater

What's Included

• 1 x GH KH hardness test kit, complete with test tube and liquid reagents for up to 80 tests

Frequently Asked Questions

What is the difference between GH and KH?
GH measures the total dissolved minerals in the water, while KH (carbonate hardness or total alkalinity) measures its buffering capacity, meaning how well it resists pH changes. This kit tests both.

What KH level should I aim for?
Keep KH at a minimum of 4 dKH at all times. A level between 6 and 8 dKH is more desirable.

What GH is best for pond fish?
For pond fish, 8 to 12 dGH is ideal. Rainwater can lower pond GH over time, so regular testing is worthwhile.

What GH do aquarium fish need?
It depends on the species. Soft water species do best at around 3 to 6 dGH, while hard water species need 10 to 15 dGH.

Should I test my tap water as well?
Yes. The GH and KH of your tap water show whether regular water changes will help maintain your levels or whether you need a buffer or mineral supplement. Tap water hardness varies with whether you live in a hard or soft water area.

How many tests do I get from one kit?
The kit provides up to 80 tests.

When can I expect delivery?

• Gauteng (Jhb/Pta) - 1-3 working days
• Nationwide (Cpt/Dbn+) - 2-5 working days
• Outlying Areas - 3-7 working days

All orders are sent via Economy Road, typically through Fastway or Internet Express Couriers*. Estimated timeframes are not guaranteed. Once the order is collected by the courier, we have no control over third-party logistics and cannot make any time promises.

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