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

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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.

Is Discontinued By Manufacturer ‏ : ‎ No


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: #915 in Pet Supplies (See Top 100 in Pet Supplies) #2 in Aquarium Test Kits


#2 in Aquarium Test Kits:


Customer Reviews: 4.8 4.8 out of 5 stars (31,066)


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 Grams


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: Saturday, Apr 25

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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Top Amazon Reviews

    • Great price kit that helps maintaining excellent water parameters
Style: Freshwater
Safe to use, good quality and has instructions. Size is great which means the kit lasts forever, it doesn’t smell. Easy to use with clear instructions. Brochure looks great and good material. Price beats all sellers.
Reviewed in the United States on March 2, 2026 by Saif
    • Accurate Results, But the Process Is a Bit Much
Style: Freshwater
This test kit is definitely accurate — I’ve used it side-by-side with other tests and it consistently gives clear, reliable readings. It covers everything I need for my freshwater tanks (ammonia, nitrite, nitrate, pH), and it’s saved me from some serious water parameter issues more than once. That said, the process isn’t exactly quick or convenient. You’ve got to measure out water into test tubes, shake bottles, time everything exactly, and match colors that sometimes look way too similar. It works, but it’s not something I look forward to doing, especially if I’m testing multiple tanks or running through every parameter at once. What I liked: - Very accurate and consistent results - Covers all the main water parameters - Plenty of tests per bottle - More reliable than strips or cheap alternatives What I disliked: - Takes a while to run a full round of tests - Color matching can be hard under certain lighting - Lots of little pieces to keep track of It’s a solid kit and does the job well — just be ready for a bit of a routine every time you use it. I keep using it because I trust the results, but I wouldn’t mind if they made the process a little more user-friendly. ... show more
Reviewed in the United States on June 9, 2025 by Ray C.
    • The best freshwater basic testing kit...
Style: Freshwater
You will find this freshwater kit is far more accurate than test strips. The soaking of a tiny doped pad method of test strips just isnt an accurate way to test. This is the industry standard water test kit that most aquarists swear by. 1st, be sure the test chemicals you get are not near expiration. You should easily be able to use this kit for up to a few years before the chemicals included lose their effectiveness. The expiration date is on the kit box and on each bottle of solution. The glass test tubes that used to be included in this kit have been replaced by plastic ones. The glass tubes made cleaning up a breeze and were far better than the plastic ones that don't clean up as well. Also the 5ml fill line is a bit difficult to see on the plastic tubes. It was always inevitable though that you would eventually break a few glass tubes before you got through the 800 tests this kit can provide. They now just assume that by the time the plastic tubes get permanently stained, you'll be on to a new test kit with new tubes. While not a deal breaker, I prefered the glass tubes. Be sure you purchase the kit best suited for the tanks or ponds you keep. This kit is the freshwater version. This kit tests pH in two different ways. If you have ph generally higher than 7.4 you use the high pH test solution. If you have pH below 7.6 youll use the standard pH test kit. This is great of you are keeping multiple tanks with different pH levels or if your one tank tends to bounce around between 7.4 to 7.6. Once you figure out which test best suits your aquariums, youll likely not use the other solution. This kit tests for total ammonia using 2 solutions in one test. Ammonia is a very hazardous chemical to your fish and plants. Use this kit to keep these levels of ammonia at or near 0. This kit tests Nitrites using 1 solution. This is the second step in the nitrogen cycle. While not as harmful as ammonia, it's still something you should strive to get as close to 0 as possible. Now some people using heavily planted and fertilized tanks will actually strive to have this level low but present. This kit tests for nitrates in two solutions for 1 test. While nitrates are not as harmful to fish as Ammonia or Nitrite, most fish keepers still strive for low readings. Long term exposures to high nitrates can still cause harm to fish. Generally youll get rid of nitrates by water changes or heavy plant growth. Many people with heavily planted and fertilized tanks prefer this value to be a little higher to feed the plants but still low to protect the fish. With this test kit testing 4 of your most important chemicals in fresh water, it is a necessity to have on hand. Test strips might be more convenient but are seldom very accurate. This liquid master test kit is the standard if you want true values at an affordable price. It comes in several varieties, depending on whether you have freshwater, marine, reef or ponds. Its a great way to see what is going on in your setup before any loss of life occurs. ... show more
Reviewed in the United States on June 7, 2024 by Don Gray
    • Good value for your money.
Style: Freshwater
Amazing kit! It helps continuously check the water parameters in my tanks to keep my fish, shrimps, and snails healthy. It's a great value for your money. It's safe to use; however, if you get the product on your hand, it will stain, lol.
Reviewed in the United States on March 24, 2026 by Mariah Nelson
    • Accurate, Reliable, and Way Better Than Test Strips
Style: Freshwater
I picked up the API Freshwater Master Test Kit when setting up my 6-gallon planted tank, and it’s been a huge upgrade over the test strips I started with. The strips were frustrating—hard to read, not very precise, and the gaps between values made it difficult to really understand what was going on in my tank. With this kit, the results feel much more accurate and consistent. I actually feel confident making adjustments based on the readings now. It’s also just a better overall experience. The process is straightforward, and there’s something oddly fun about it—it definitely gives off “mad chemist” vibes in the best way. ... show more
Reviewed in the United States on March 24, 2026 by Kaleigh

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