

💧 Keep your aquarium thriving with precision water testing—because your fish deserve the best!
The API GH & KH Test Kit is a professional-grade freshwater aquarium water test kit designed to accurately measure general hardness (GH) and carbonate hardness (KH). It includes two bottles of testing solution, a color card, and two glass test tubes with caps, enabling easy and reliable weekly monitoring of water quality. This kit helps prevent fish stress and loss by ensuring water hardness matches the natural habitat of your fish, making it an essential tool for any serious aquarium keeper.













| ASIN | B003SNCHMA |
| Batteries Included | No |
| Batteries required | No |
| Best Sellers Rank | 1,274 in Pet Supplies ( See Top 100 in Pet Supplies ) 2 in Aquarium Test Kits |
| Customer Reviews | 4.7 4.7 out of 5 stars (5,477) |
| Date First Available | 8 Aug. 2009 |
| Item Weight | 70.8 g |
| Item model number | 58 |
| Number of Items | 1 |
| Pet Type | Fish |
| Product Dimensions | 6.99 x 4.13 x 13.02 cm; 70.87 g |
| Quantity | 1 |
| Size | 1 Count (Pack of 1) |
| Volume | 1.25 |
M**S
Superb products.
Superb product. API is one of my resources for many of my aquarium essentials. Never had any problem with any of there items. Great value for money, with many products giving you size options for what you need. All products from medicated to water parameters and plant care. These products are made with an ease of understanding for what that purpose is and will help you on your fish keeping journey.
N**7
Seems to work
Seems to be OK but I don't know how accurate the test results are - I have to rely on them being accurate.
E**Z
Essential for Healthy Fish Tank
This API GH & KH test kit is a must-have for any freshwater aquarium owner. It's easy to use and gives clear, reliable readings for general and carbonate hardness. Keeping these levels balanced is crucial for fish health. Highly recommend for maintaining a stable tank environment
S**E
Fiddly to use, but appear accurate and easy to read
We use rain water for replacing the water in our aquariums, which naturally is very clear unlike our tap water at times. One problem however is that rain water lacks nutrients and carbonate hardness, so I need to add supplements. This GH and KH kit lets me keep an eye on these levels. The kit includes two bottles and two test tubes with caps. At a first glance it appears simple to use, i.e. with a 5ml sample in the test tube, add a drop of solution, cap and shake, then repeat until the colour changes. In reality, the cap is very stiff to place on the test tube. After repeating the steps a few times, some liquid ran down the outside of the test tube and as I tried capping it, it slipped from my fingers, flew across the table and smashed on the floor. Once I managed to test the KH and GP and using a paper towel to dry the test tubes before capping after each drop, the test reading itself is very simple - The colour changes from blue to yellow for the KH reading or from green to yellow for the GH reading. It includes a chart that shows the readings for the number of drops added. Personally I would prefer if it included a bung instead of a cap as it is quite tedious trying to pull off and replace the stiff cap after each drop, particularly when it can take 6 to 9 drops to complete each test. The guide mentions that the bottles must be held vertically upside down for accuracy, so I'm not sure about the accuracy with being unable to fully invert the bottle without it releasing multiple drops. With other test kits, I need to squeeze the bottle to release drops, where as the bottles with this kit starts releasing drops before it is fully inverted. There is also a warning to wear protective gloves, protective clothing, eye protection and face protection and to only use outdoors or in a well-ventilated area.
A**R
Testing of soft water levels
Great item to test ph levels in water, especially when tap water is soft water
J**E
Does exactly what is says.
Great value for accurate results. The instructions can be abut misunderstood but after searching some forums online, it’s easy to understand.
D**P
I recommend
Never failed. I always have this testing kit on hand.
R**K
Easy and fun to use hardness test.
I've found this test to be easy to use and it is fun observing the colour changes. My tapwater and most clean local water sources seem to be rather hard at 10 degrees GH. I am using collected rainwater (measuring under 2 degrees GH) to dilute my tapwater and bring the hardness down. I did ask a friend to bring me water in a container as his water is soft at 3 degrees GH. However the pH of his water is high at 7.8 and as my fish prefer soft acid conditions I think a pH of 7.8 may be undesirable. I'm unsure why I should measure KH as well but I have done so for completeness and this test is just as simple.
K**S
This is an essential test kit for fish keeping as it will determined the general hardness and carbonate hardness in the water. I use ro water for my fresh water tanks which gives the pure form of water. Then I mix general hardness enhancing solution like seachem equilibrium or seachem replenish to make water with desired gh level. Then I use seachem alkaline buffer and acid buffer accordingly to maintain the proper carbonate hardness and ph for the specific species tank I'm using the water. This kit comes handy in checking the final gh and kh levels before adding the water in the tanks..
T**R
easy to use and accurate. good to monitor hardness in fresh water aquarium
B**P
Easy to use and readings of both gh and kh very accurate no guessing or matching colours
D**H
Muy bien producto a precio racionable, dar bien mediciones comprobado contra otras test kits mucho mas caro y todos muestra la misma nivel de GH y KH. Muy facil de usar aunque con agua muy blanda como el mio hay que mirar desde arriba contra algo blanco para ver el color de inicio en test GH.
R**O
I recently started using the API GH & KH Test Kit for my freshwater aquarium, and I must say it has been an incredibly helpful tool for maintaining a healthy tank environment. Here’s a detailed review based on my experience: **Ease of Use:** The test kit is very straightforward and user-friendly. The included instructions are clear and easy to follow, even for beginners. Testing both General Hardness (GH) and Carbonate Hardness (KH) takes just a few minutes, and the color changes in the water make it easy to get accurate results. **Accuracy:** The API test kit provides reliable and consistent readings. I compared the results with a digital meter, and they matched up perfectly. Knowing the GH and KH levels helps me adjust my water chemistry for optimal conditions, especially for sensitive fish like cichlids and shrimp. **Functionality:** Having a tool that measures both GH and KH in one kit is incredibly convenient. GH helps monitor essential minerals for fish health, while KH is crucial for stabilizing pH levels. This kit makes it easy to detect changes early, helping prevent pH swings or stress in my fish. **Value for Money:** For the price, you get a high-quality, reliable kit that will last quite a while. The included bottles have enough solution for numerous tests, making it a cost-effective option for regular water monitoring. **Overall Impressions:** The **API GH & KH Test Kit** is a must-have for any freshwater aquarium enthusiast. It’s easy to use, highly accurate, and helps ensure your water parameters are within the right range for your fish and plants to thrive. I highly recommend it for hobbyists of all experience levels. **Rating: 5/5** Reliable, accurate, and easy-to-use water testing for a healthy aquarium!