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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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Availability: In Stock.
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Arrives Tuesday, Jun 23
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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: #5,080 in Pet Supplies (See Top 100 in Pet Supplies) #7 in Aquarium Test Kits


#7 in Aquarium Test Kits:


Customer Reviews: 4.8 4.8 out of 5 stars (31,163)


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: 6.54 x 4.96 x 4.17 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: Tuesday, Jun 23

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

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.
    • 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
    • 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
    • Easier than high school chemistry, but similar lab rules apply
Style: Freshwater
Have you passed high school chemistry? (And by pass, I mean be able to follow the rules while in a lab?) Then great! You'll have no problem using this test kit! However, be aware the instructions are like stupid tiny. I'm only 20 and even with reading glasses on top of my regular glasses these instructions are tiny. API offers a .pdf version of the instructions on their website, so I recommend those more than the little booklet. I also recommend one of those little syringes for like pet medication or human medication. It makes getting the water in the tubes a lot easier and with good accuracy. A lot of reviews mention the test tube caps not being tight when capped. I haven't had this problem, but also when I invert the tubes, I hold my finger on the cap and at the bottom of the test tube. This was a habit I picked up in college chemistry because sometimes it better to be safe than sorry. Gloves aren't necessary, but if you feel safer (especially since some of the chemicals are corrosive) then ball out with gloves! A lot of reviews also mention the nitrate test. I'm not a biologist, so I can't say the accuracy, however, make sure you read the instructions REALLY good as it's completely different than the others. You add 10 drops of solution bottle 1, shake the tube, shake solution bottle 2 for 30 seconds, add 10 drops, shake the tube for a minute, then wait the 5 minutes to develop. My few complaints is why I'm giving this a 4/5 stars because I feel like they really hinder the product. There's simply not an appropriate number of tubes. There's 5 tests, but only 4 tubes. Beyond that, they should really have 6 tubes since accidents are super prone to happen with tiny test tubes like this. Even beyond this, I feel a silicone or even plastic caps that screw with a rubber seal would be icing on the cake to eliminate the leaking and hardening issue. I'm also not buying API's 24 kit of tubes for a few extra tubes, that's just ridiculous. My next complaint is I believe they should add the GH and KH test in with this kit. pH, GH, and KH are usually all related to each other, so having that in the kit rather than paying $10 separately for it. I'd rather get it with the kit and pay 5-7 dollars more for the kit. To feed off some other reviews, adding the syringe like I mentioned would be better too since a lot of people probably won't think about it. Finally, I think a chlorine test would be great since it's toxic to most fish. However, I do believe in giving credit where credit is due and this kit is affordable which is great for those just starting to get into the hobby! I think the hobby is gate-kept by super expensive products, so having something like this that isn't $50+ is really helpful for those just starting out! I also love the size of this kit, it's easy to store. No test kit will probably ever be 100% accurate nor will they probably ever match up, but I feel this is good for America's market. I say that because I've used Sera, which is imported from Germany, and it's super nice with detailed and intense instructions which makes the tests feel a bit more accurate than this high school chemistry project. (Sorry API). However, the $80 keeps me from repurchasing and instead, buy this one. So, I guess that's the magic of capitalism and having other bills to pay rather than spending $80+ on a water testing kit. Even after being in the hobby since I was in middle school, I feel a lot of the prices in this hobby prevent people from advancing further and wanting to get into saltwater, reefs, or ponds. I stick with freshwater simply because it's the cheapest and easiest. Overall, recommend. 7/10, just be aware and take some of the recommendations some reviewers have already said and it should be smooth sailing. ... show more
Reviewed in the United States on August 22, 2021 by Hayley
    • Would recommend
Style: Freshwater
Great to have on hand and use often
Reviewed in the United States on May 19, 2026 by StaceyKay
    • 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
    • Not sure this measurement chart was printed correctly. 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 Reviewed in the United States on April 18, 2026 by J. Tanner Netterville

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