GH & KH TEST KIT

When keeping freshwater fish and plants, the general hardness (GH) and carbonate hardness (KH) of aquarium water should match their natural habitat. The API GH & KH TEST KIT helps you duplicate the natural habitat of your fish to prevent stress, keeping them healthy!

Sizes

Contains 2 test bottles, easy-to-ready instructions, and test tubes

What is Carbonate Hardness (KH)?

Carbonate hardness, also known as alkalinity, is the measure of carbonate and bicarbonate concentrations dissolved in water. These minerals are present in municipal, well, and bottled water. The level of carbonate hardness in tap and bottled water depends on the source of the water and the treatment processes it has undergone. Carbonate hardness helps stabilize pH in the aquarium. An aquarium with a low KH level will tend 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.

What is General Hardness (GH)?

General hardness is the measure of calcium and magnesium ion concentrations dissolved in water. These minerals are present in municipal, well, and bottled spring water. The level of general hardness in tap and bottled water depends on the source of the water and the treatment processes it has undergone. Hard water is high in calcium and magnesium, while soft water is low in these minerals.

How do I care for and clean my test tubes?

Once the test has completed, it is important to rinse the test tube with water right away so that the contents don’t stay in the test tube. This will make sure that the reagents don’t cause anything to stick to the sides of the test tube, which could cause staining over time.

Simply run the water, open the test tube gently (do not twist the cap), and allow the water to dilute and rinse the contents out of the test tube. Avoid getting the contents of the test tube on your skin.

If you find that you have forgotten reagent within your test tube for a long period and the color is sticking to the tube, you are able to use a small bottle brush (and some API Safe & Easy cleaning spray) to gently wash the inside of the tube. Avoid the use of soap, as soap residue could be introduced back into the aquarium when filling the test tube at next use, which is something that could be harmful to your fish.

Replacement test tubes are also available for purchase from online retailers, should you need additional test tubes.

How hard do I shake the test tube when performing the tests?

While it is important to shake the indicated reagent bottles very vigorously, you should be gentler when shaking the test tubes during testing. Before shaking, make sure that the cap is closed tight. Place a finger or thumb on top of the cap, to make sure it cannot come undone during use. The goal of this shaking step is to mix the contents of the tube together and this can be accomplished by simply inverting the test tube, back and forth every 1-2 seconds, for the indicated amount of time.