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API Freshwater Master Test Kit 800-Test Freshwater Aquarium Water Kit, White, Single, Multi-Colored

  • Based on 31,417 reviews
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Style: Freshwater


Features

  • Contains one (1) API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, including 7 bottles of testing solutions, 1 color card and 4 tubes with cap
  • Helps monitor water quality and prevent invisible water problems that can be harmful to fish and cause fish loss
  • Accurately monitors 5 most vital water parameters levels in freshwater aquariums: pH, high range pH, ammonia, nitrite, nitrate
  • Designed for use in freshwater aquariums only
  • Use for weekly monitoring and when water or fish problems appear

Description

Most water problems are invisible to the eye. Quickly measure and modify the six aquarium levels that are most important to the health of your freshwater fish with the API FRESHWATER MASTER TEST KIT. To stay healthy and thrive, fish need properly balanced levels of ammonia, pH, high range pH, nitrite and nitrate. These levels can change rapidly and create harmful conditions when fish waste, uneaten food or other organic matter accumulate, or when untreated water is added. If left uncorrected, all of these can be harmful or even fatal to fish, with consequences such as reduction of oxygen, increase in stress and higher risk of disease. The API FRESHWATER MASTER TEST KIT measures these six parameters with scientific accuracy and provides professional results. It comes with four test tubes, a holding tray and computer calibrated, laminated color card. Just fill the test tubes, add the test drops and compare results to the color card. Then follow the recommendations on the card if action is required. With API aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For almost 60 years API has developed premium solutions with proven and effective results for your family and ours. API offers a range of testing kits, water conditioners, and nutritionally superior food, because we’re dedicated to making a better underwater world. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. At API, we understand the rewards and relaxation of fishkeeping because we have a passion for fish too.

Product Dimensions ‏ : ‎ 9.13 x 3.5 x 4.65 inches; 1.15 pounds


Item model number ‏ : ‎ 34


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ June 20, 2004


Manufacturer ‏ : ‎ Mars Fishcare


Best Sellers Rank: #1,903 in Pet Supplies (See Top 100 in Pet Supplies) #3 in Aquarium Test Kits


#3 in Aquarium Test Kits:


Customer Reviews: 4.8 4.8 out of 5 stars (31,417)


Item Weight: 1.15 pounds


Department: Unisex-Adult


Manufacturer: Mars Fishcare


Item model number: 34


Date First Available: June 20, 2004


Item Package Dimensions L x W x H: 6.69 x 5.12 x 4.33 inches


Item Dimensions LxWxH: 9.13 x 3.5 x 4.65 inches


Item Weight: 521.63 g


Brand Name: API


Target Audience Keyword: fish


Directions: Follow the instructional booklet directions for individual testing of each water parameter, and test weekly for best results.


Warranty Description: Warranty


Model Name: API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, White, Single, Multi-colored


Color: Multi-color


Size: Single


Material: Plastic


Number of Items: 1


Style: Freshwater


Included Components: API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, White, Single, Multi-colored


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 28 – Oct 4

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • I will buy it again
Style: Freshwater
Review Image by Jesse Garcia
Review Image by Jesse Garcia
Review Image by Jesse Garcia
Review Image by Jesse Garcia
Review Image by Jesse Garcia
Review Image by Jesse Garcia
Easy to understand the instructions. Comes in a portable case which is a perfect caddy to go from one aquarium to the next. No scent that I detected. The case is durable and has an easy storage system that holds each vile. The colors are easy to get a reading to match against and each bottle has a different color for color coded instructions. The helped me adjust my water parameters to better suit my tropical fish. Very effective. ... show more
Reviewed in the United States on July 4, 2026 by Jesse Garcia
    • Good
Style: Freshwater
This kit will last you a while, the material is good and it is very simple and easy to use. It doesn’t smell bad at all. The tubing is plastic, and I recommend handling with gentle care because you can rip off the lids if you mis treat it, but other than that the whole kit is good. The color comes out pretty precise, and the instruction manual tells you everything you need to do especially for people’s first time using it. Personally in the back of the book there are blank pages, and I like writing the date and the results every time I water test. Just a little tip! ... show more
Reviewed in the United States on August 8, 2026 by Haylise
    • Every aquarist should have this!
Style: Freshwater
Review Image by ✨Ally✨
This is a crucial need for EVERY aquarist out there. This kit is worth the time and money and it lasts me foreverrr. Will forever be buying refills. This kit is so beneficial in cycling your tank and checking for ACCURATE water parameters. It’s easy to use and I love feeling like a scientist when testing. Will forever recommend this product to those who need it. ... show more
Reviewed in the United States on March 23, 2026 by ✨Ally✨
    • Must have kit for monitoring fish tank
Style: Freshwater
Got this kit for monitoring my goldfish tank. Very easy to use with clear instructions. Overall very satisfied and think this is a very suitable test kit to start with. This kit tests for 2 things. (1) PH levels and (2) Ammonia, Nitrite, and Nitrate levels (i.e. the Nitrogen Cycle). The Nitrogen cycle as related to a fish tank is as follows... Your fish gives off waste products, which Ammonia is a major component. When Ammonia levels in the tank go to high the fish can get burns, sick and can die. At some point your tank should develop bacteria that convert the Ammonia to Nitrite (this bacteria can live in the gravel and the filter. Also this bacteria is killed by tap water that has chlorine present so this is why you don't wash gravel with tap water. Also this is why you should not change all filter elements at once as you may be eliminating too much of your bacteria colonies). Once the bacteria that do this develop a large enough colony your ammonia levels should go to zero. Before the colony of bacteria is developed your tests for Ammonia should show some level present. You want to make sure that the level does not go to high. To reduce Ammonia levels you can either do water changes, use a filter that removes Ammonia or there are additives that can be added to reduce the levels as well. The next step is the bacteria converts the Ammonia to Nitrite. Nitrite levels if they go too high are bad for fish. Initially Nitrite levels will tend high (similar solution for excessive Ammonia levels will work for Nitrite as well). Eventually a colony of bacteria will develop that convert Nitrite to Nitrate. Once the colony reaches maturity your Nitrite levels should come up as zero on your tests. The final step (well not final if you use plants, which is more complicated) is as mentioned above the Nitrite being converted to Nitrate. When the bacteria colonies are fully removing all the Ammonia and Nitrite the tank is called cycled. At this point the major concern is that Nitrate levels should not go too high. The fortunate thing is that fish can tolerate relatively high levels of Nitrate as compared to Ammonia or Nitrite. I would think most cases where fish are not faring well, probably the Ammonia or Nitrite levels are high and the Nitrate is fine. In any case you will need to test for Nitrate probably no more frequently than every few weeks to few months (depends on your tanks size and number of fish) to make sure the levels are not getting to high. The solution for high levels is the same as for Ammonia or Nitrite, namely water changes, filtering, and additives (I have stayed away from additives but they are an option). This kit gives you everything you need to test for this critical cycle and is probably all you need for most fish tanks to help you keep your fish healthy for a long time. ... show more
Reviewed in the United States on September 1, 2013 by matt1234
    • Great product, just inconvenient
Style: Freshwater
It's a must-have for aquarists and it's very accurate, but i think buying the test strips are more convenient and quicker than breaking this out every time. I only bought it, since it was on sale
Reviewed in the United States on July 23, 2026 by Tanner Mabry
    • Not sure this measurement chart was printed correctly.
Style: Freshwater
Review Image by J. Tanner Netterville
Does this scale look a little wonky to anyone else? The 7.6 and the 7.4 seem to be out of order, but also the color gradation jumps dramatically between the ones labeled 7.6 and 7.4. It's almost like the labels were printed backwards? Edit: I'm dumb. those are two different ph test scales. There are two separate PH test reagents. All the tests seem to work just fine, and after realizing my mistake, the color chart is fine. There are still some typos and incomplete sentences in the instructions, but everything was still clear enough to follow. I'm gonna have to get an alternate pH test for a sanity check here. which doesn't inspire confidence for the rest of the test get either, as well as the typos and incomplete sentences in the instruction manual. at least it is cheap and it's giving me some metrics to go off of. ... show more
Reviewed in the United States on April 18, 2026 by J. Tanner Netterville
    • Accurate test that takes around 10 minutes to do
Style: Freshwater
Review Image by Ryott
Review Image by Ryott
I recently bought my first fish tank, Tetra ColorFusion 20 Gallon Aquarium Kit, and quickly learnt about the importance of testing the water. In case you do not know, a new fish tank needs to go through a cycle where the waste becomes ammonia (dangerous for fish); then, bacteria will grow and convert it into nitrite (also poisonous); and then additional bacteria will grow and convert it into nitrate (not dangerous). To ensure that your fish survive in the long term, you need to monitor these three parameters and make sure that the ammonia and nitrite do not remain high for too long. I decided to buy this kit so I can do tests every two days, as I read that it is more accurate and inexpensive than using strips. Overall, I am very happy with it. Every test I do takes just a few drops. The manufacturer claims 800+ tests, but be careful that is the total number (adding all the different tests together). If you look at just one type of test, like nitrate, the one that requires the most drops, you will be able to do 50-60 tests (as another reviewer has calculated). Most of the tests are very easy to do, with the exception of nitrate, that requires shaking the bottle for 30 seconds and the water sample for 1 minute, and it is somehow tiring. I found running all the tests took me around 10 minutes. I have taken a video so you can get an idea of the "effort involved". Overall, I am very happy with this kit. Over the last few days I have seen the ammonia climbing, then nitrite and now nitrate, so I can perfectly understand what is going on in my tank! ... show more
Reviewed in the United States on January 21, 2017 by Ryott
    • Must have
Style: Freshwater
If you're even just getting into the fish keeping hobby, this is a must have. In my experience test strips are inaccurate and spotty at best, but with this Master Test Kit from API is effective and you will know what is going on with your tank. I only wish this test kit included the GH and KH tests as well but they are available to buy separately. ... show more
Reviewed in the United States on May 10, 2026 by JJT

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