API GH and KH Test Kit for Freshwater Fish and Plant

API GH and KH Test Kit for Freshwater Fish and Plant

The API GH and KH Test Kit for Freshwater Fish and Plant is a water test kit that measures the general hardness (GH) and carbonate hardness (KH) of your aquarium water. It is made for freshwater fishkeepers and planted-tank owners who want their water to reflect the natural habitat of their fish and plants.

Key Benefits

• Measures both general hardness (GH) and carbonate hardness (KH) in one kit, so you can check the two key mineral values of your tank water.
• Helps you match your aquarium water to the natural habitat of your freshwater fish and plants, which helps avoid unnecessary stress for your fish.
• Lets you keep an eye on KH, which helps stabilise pH. This is useful in tanks with low KH, where pH can shift quickly if the water isn't monitored.
• Helps you understand your source water. Hardness levels in tap and bottled water vary with where the water comes from and how it has been treated.
• Comes with easy-to-read instructions, so the kit is straightforward to use for newcomers and experienced hobbyists alike.

Understanding KH (Carbonate Hardness)

Carbonate hardness, also known as alkalinity, measures the carbonate and bicarbonate dissolved in water. These minerals are present in municipal, well and bottled water. The level in your tap or bottled water depends on its source and the treatment it has undergone.

• KH helps stabilise pH in the aquarium.
• An aquarium with a low KH level tends to be acidic.
• Aquariums with very low KH are subject to rapid pH shifts if not monitored carefully.
• Water with a high KH level usually has a high pH.

Understanding GH (General Hardness)

General hardness measures the calcium and magnesium ions dissolved in water. These minerals are present in municipal, well and bottled spring water, and the level in tap or bottled water depends on the source and the treatment process it has been through.

• Hard water is high in calcium and magnesium.
• Soft water is low in these minerals.

How to Use

Fill the glass test tubes with your aquarium water and follow the step-by-step instructions supplied in the kit for each test.

Suitable For

• Freshwater aquariums housing fish and live plants.
• Hobbyists who want to compare their tap, well or bottled water against the conditions their fish and plants come from.
• Anyone keeping an eye on pH stability by tracking carbonate hardness.

What's Included

• 2 test bottles
• Easy-to-read instructions
• Glass test tubes

Frequently Asked Questions

What does the GH and KH test kit measure?
It measures general hardness (GH), which is the calcium and magnesium dissolved in the water, and carbonate hardness (KH), also called alkalinity, which is the carbonate and bicarbonate dissolved in the water.

Why does KH matter for pH?
Carbonate hardness helps stabilise pH. Low KH tends to make an aquarium acidic and can lead to rapid pH shifts, while high KH usually goes hand in hand with a high pH.

Is this kit suitable for planted tanks?
Yes. It is designed for freshwater fish and plants, helping you match your water to the natural habitat of both.

Will my tap water have the same hardness as bottled or well water?
Not necessarily. Hardness in municipal, well and bottled water depends on the water source and how it has been treated, which is why testing your own water is worthwhile.

What is the difference between hard and soft water?
Hard water is high in calcium and magnesium, while soft water is low in these minerals. GH is the value that shows where your water sits.

What comes in the box?
The kit contains 2 test bottles, easy-to-read instructions and glass test tubes.

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.

If you prefer a faster 🚀 shipping option, we also offer The Courier Guy during checkout in the dropdown selection. Please note that this option is not free, and you must choose it to use it. Please pay careful attention to the cutoff times and delivery timeframe for these options during checkout.

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• Bob Box: Collect within 2 days of receiving your collection notification.
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