API GENERAL/CARBONATE HARDNESS KIT
Helps monitor water quality and prevent invisible water problems that can be harmful to fish and cause fish loss.
Accurately measures GH & KH in freshwater aquariums.
Water hardness is a measure of the dissolved mineral content of water and should match fish natural habitat to prevent fish stress and keep them healthy.
Use for weekly monitoring and when water or fish problems appear.
| Parameter | Measurement |
|---|---|
| GH (General Hardness) | Measured in dGH |
| KH (Carbonate Hardness) | Measured in dKH |
FAQ
How often should I use this kit for water testing?
Use the kit weekly for routine monitoring, or more frequently if you notice changes in water conditions or fish behavior.
Can this kit be used for saltwater aquariums?
No, this kit is designed for freshwater aquariums only.
What does GH and KH measure in water?
GH measures the total dissolved mineral content, while KH measures the carbonate hardness, which affects water’s buffering capacity.

Joe Hudson –
This kit has been very reliable for tracking water hardness in my 100-gallon tank. I use it every two weeks and it helps me catch changes early. My fish have stayed healthy without any stress signs.
Olivia Gray –
Easy to use and gives clear results. I noticed a drop in KH after a water change and adjusted my water chemistry right away. It’s a small but useful tool for maintaining stable conditions.
Edward Paige –
I’ve used this kit for over a year now and it’s consistently accurate. It’s helped me avoid fish loss during seasonal water fluctuations. The instructions are simple and the results are easy to interpret.