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API REEF MASTER TEST KIT Reef Aquarium Water Test Kit 1-Count

4.5 4.5 out of 5 stars 1,713 ratings

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Reef

Purchase options and add-ons

  • Contains one (1) API REEF MASTER TEST KIT Reef Aquarium Water Test Kit 1-Count, including 7 bottle of testing solution, 2 color cards and 4 test tubes with cap
  • Helps prevent invisible water problems that can be harmful to fish and cause fish loss
  • Accurately monitors 4 most vital water parameters levels in reef aquariums: Calcium, carbonate water hardness, phosphate and nitrate
  • Designed for use in reef aquariums only
  • Use for weekly monitoring and when water or fish problems appear

Customer ratings by feature

Easy to use
4.0 4.0
Easy to read
4.0 4.0
Accuracy
3.7 3.7

Compare with similar items

This Item
API REEF MASTER TEST KIT Reef Aquarium Water Test Kit 1-Count
API REEF MASTER TEST KIT Reef Aquarium Water Test Kit 1-Count
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Price-31% $34.97
List:$50.48
-29% $35.97
List:$50.48
$15.48-33% $12.33
List:$18.28
-29% $35.97
List:$50.48
Delivery
Get it as soon as Sunday, Mar 31
Get it as soon as Sunday, Mar 31
Get it as soon as Sunday, Mar 31
Get it as soon as Sunday, Mar 31
Get it as soon as Sunday, Mar 31
Customer Ratings
Easy to use
4.0
4.4
4.4
4.6
4.6
Easy to read
4.0
4.2
4.4
4.5
4.5
Accuracy
3.7
4.0
4.3
4.1
4.6
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Amazon.com
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Looking for specific info?


From the manufacturer

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test

Testing the Waters

In order for fish to thrive, water must be similar to that which could be found in their natural environment. Poor water quality can cause fish stress, illness and even loss. Most common water quality parameters are Ammonia, Nitrite, Nitrate, and pH. All may vary over time and all are invisible to the eye which is why it is important to test weekly. Testing aquarium water weekly will aid in keeping your most important water parameters within the proper range for your aquarium. Choose from a wide range of API testing options, such as our popular FRESHWATER MASTER TEST KIT or 5-IN-1 TEST STRIPS, for accurate water evaluation. Regular testing will help you easily determine your aquarium conditions.

Find Your Ideal Testing Style!

Test

Test

Test

Test

Your API Test Options

Choose the test method that works best for you. Whether you’re a bit pressed for time, or you prefer to measure your parameters on a more in-depth scale, or you only need to test one or two specific parameters, API has what you need!

Dip and Read

Just dip a 5-in-1 TEST STRIP in your aquarium, swirl twice, and compare to our color chart for fast and accurate results.

The Scientific Approach

For more detailed analysis, use the FRESHWATER MASTER TEST KIT, POND MASTER TEST KIT, SALTWATER MASTER TEST KIT, or REEF MASTER TEST KIT for precise readings of parameters.

Pick One (or Two)

Need to check your phosphate levels? What about ammonia? API offers specific test kits to test many different parameters, from general hardness and copper to pH and nitrate. Grab the one you need for a streamlined approach to testing.

Test Test Test Test Test Test
API QUICK START API AMMO-LOCK API pH UP API pH DOWN API NITRA-ZORB API PHOS-ZORB
Customer Reviews
4.7 out of 5 stars
12,059
4.6 out of 5 stars
4,829
4.6 out of 5 stars
611
4.5 out of 5 stars
1,620
4.4 out of 5 stars
2,517
4.5 out of 5 stars
411
Too much nitrites?
Too much ammonia?
Inappropriate pH levels?
Too much nitrates?
Too much phosphates?
test

Making a Better Underwater World

At API, we understand the rewards and relaxation of fishkeeping because we have a passion for fish too. 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.

Product Description

Measure the most important reef aquarium levels including calcium, carbonate hardness (KH), phosphate and nitrate with API REEF MASTER TEST KIT. Proper balance is key to the overall health of reef inhabitants. Corals and reef invertebrates like shrimp, crabs and encrusting algae require calcium to grow and proper levels of carbonate hardness to prevent harmful fluctuations in pH. Excess phosphate, which comes from fish waste, uneaten food and other decaying organic matter as well as tap water, can cause algae blooms and affect healthy growth of hard corals. High nitrate levels from fish waste and organic compounds can cause fish disease and algae blooms. The API REEF MASTER TEST KIT comes with four different tests that are specifically calibrated to measure these levels in reef aquariums. 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 details

  • Is Discontinued By Manufacturer ‏ : ‎ No
  • Product Dimensions ‏ : ‎ 7 x 5.75 x 4.75 inches; 1.1 Pounds
  • Item model number ‏ : ‎ 402M
  • Department ‏ : ‎ Unisex-Adult
  • Date First Available ‏ : ‎ July 25, 2005
  • Manufacturer ‏ : ‎ Mars Fishcare
  • ASIN ‏ : ‎ B001D6Z7QW
  • Country of Origin ‏ : ‎ USA
  • Customer Reviews:
    4.5 4.5 out of 5 stars 1,713 ratings

Important information

Ingredients

Includes Calcium, Carbonate Hardness, Phosphate, Nitrate Test Bottles, Instructions, 4 Glass Test Tubes And Color Charts.

Directions

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

Legal Disclaimer

Must ship via ground shipping please allow a couple extra days for transport

Customer reviews

4.5 out of 5 stars
4.5 out of 5
1,713 global ratings

Customers say

Customers like the performance, quality and ease of use of the pet supplies. For example, they mention the test works well, the results are spot on and the kit is well-appointed. They appreciate the value. That said, some complain about the leakage and color issues. Opinions are mixed on accuracy.

AI-generated from the text of customer reviews

90 customers mention73 positive17 negative

Customers like the quality of the pet supplies. For example, they say it's a nice test kit, well-appointed, and reliable. Some mention that the color key on the back bled together. That said, most are happy with their purchase and recommend it to others.

"...gallon breeder reef tank, and so far they have been easy to use and reliable...." Read more

"...The Kit is solid, the only negative is that one of my test tubes leaked a little but nothing major...." Read more

"This test kit is okay, it does it's job. However, shortly after my purchase, i realized something important...." Read more

"nice starter test kit until you an afford the better ones..." Read more

67 customers mention56 positive11 negative

Customers find the pet supplies easy to use. They mention the instructions are clear and easy to read. They also say the tests are simple to do and understand. Customers also say that the process is easy to determine and calculate. Overall, customers are satisfied with the ease of use and accuracy of the product.

"Simple and quick" Read more

"...I also like that these tests are simpler to preform than most of the others, so thats a real plus." Read more

"I really like the ease of use" Read more

"...The Good: The API tests are simple, the directions are good, and the diverse group of tests makes it a great value...." Read more

52 customers mention42 positive10 negative

Customers like the value of the pet supplies. They say it's a good price, cheaper than using strips, and an inexpensive test kit that lets you know if something is going wrong.

"This kit is very accurate as mentioned in the title and is cheaper than my local fish store. I only wish that they included a second pipette." Read more

"...the directions are good, and the diverse group of tests makes it a great value. Colors are easy to readThe Average:..." Read more

"...I also like the price--since there are four tests included, each test is around $5, about a quarter the price of competitors...." Read more

"...I realize that these are quite a bit cheaper than other test kits, and have varied options to test all parameters, but it's not worth it...." Read more

43 customers mention33 positive10 negative

Customers like the performance of the pet supplies. They say the test works well, the results are spot on, and it delivers results within an acceptable tolerance. Some customers also mention that the KH does adequately well. Overall, most are happy with the performance and value of the product.

"But everything seems to be working well...." Read more

"...This test kit will deliver results within an acceptable tolerance...." Read more

"The results are spot on. I actually took some water to my LFS to compare and they had the same results...." Read more

"The tests are a bit tedious and time consuming, but worth it for the added accuracy over test strips...." Read more

75 customers mention33 positive42 negative

Customers are mixed about the accuracy of the pet supplies. Some mention it works well and is accurate for what it tests, while others say that the phosphate test kit is not accurate. The Calcium test is consistently off by 100 ppm compared to independent testing.

"Buyer beware, these online kits (particularly the KH) is inconsistent and severely in accurate when compared to those bought elaewhere...." Read more

"This kit is very accurate as mentioned in the title and is cheaper than my local fish store. I only wish that they included a second pipette." Read more

"...Also, the saltwater test kit does not have the calcium and hardness tests that the reef kit has, so you really need both test kits for most marine..." Read more

"...: The API tests are simple, the directions are good, and the diverse group of tests makes it a great value. Colors are easy to read..." Read more

27 customers mention3 positive24 negative

Customers are dissatisfied with the leakage of the pet supplies. They mention that the little snap-tight lids leak, and the chemicals spill all over the place. Some say that the ink dripped all over their hands. The lids for the vials it came with don't seal all the way, and chemicals spill everywhere.

"...First of all, the test tubes all leak because the cap doesn't fit for a leakproof seal...." Read more

"...to" video for using this test kit and has the chemicals dripping all over his hands... maybe that explains the arm growing off of his neck......" Read more

"...Also, as others have said, the little snap-tight lids leak. Fortunately she started with calcium and it just irritated her skin...." Read more

"...with the other API test kits, the major flaw is how the vials leak when you mix the liquids. No matter how tight you hold the lid, they always leak." Read more

17 customers mention3 positive14 negative

Customers find the color of the pet supplies to be hard to read and distinguish. They mention that there is no color chart or instruction booklet. Some customers also mention that the color gradients are hard to see.

"...Some of the color gradients are hard to distinguish, however it's better than test trips for the most part...." Read more

"...what level things are at, because sometimes the color in the tube doesn't match the paper, and other times it looks exactly like more than one...." Read more

"...to watch YouTube videos in order to use this as there was no color card or test kit included in my kit...." Read more

"...my salt water tank levels should be at.. I put the drops in, it changes colors and now what?..." Read more

Kit reagents faulty (dilute or less active) compared to same API dKH test from LFS.
4 Stars
Kit reagents faulty (dilute or less active) compared to same API dKH test from LFS.
Buyer beware, these online kits (particularly the KH) is inconsistent and severely in accurate when compared to those bought elaewhere.I bought this 4 test reef kit in large part to monitor my KH. I very early killed my reef because the include KH testing solution is very diluted.A few days before my kit arrived my local fish store measured a dKH of 9.0With a goal of 10-11, I added some buffer equal to what it took to go from 8 to 9 dKH. Boy was I surprised when I reached drop 17 and it still hasn't change color at all.Tested multiple times after a couple of water removals, the lowest read I got was 13 dKH.The exact same water was actually 8. This was done by using his own store bought API reef kit.The worst part is that Amazon does not allow returns of this product, and there's no way to swap out this one bottle because there is no 3rd party vendor I'm directed to by Amazon to discuss replacments, nor any person or place to complain to about this faulty equipment (except by writing this review).------------Update: I found the place to talk with amazon about this item, and the issue has been resolved because they'll send me a replacement.So on the one hand you may need to double check the strength of reagenta with a friend's reef kit - but Amazon is actually pretty helpful and generous when you are finally connected to a real person on the phone.So, -1 star for this bad KH testing batch and the near miss to my tank ecosystem, but that still leaves 4 stars for this kit that is great for the beginner hobbyist.Good luck!
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Top reviews from the United States

Reviewed in the United States on March 20, 2024
Reviewed in the United States on November 14, 2011
15 people found this helpful
Report
Reviewed in the United States on October 26, 2023
Reviewed in the United States on September 29, 2020
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4.0 out of 5 stars Kit reagents faulty (dilute or less active) compared to same API dKH test from LFS.
Reviewed in the United States on September 29, 2020
Buyer beware, these online kits (particularly the KH) is inconsistent and severely in accurate when compared to those bought elaewhere.

I bought this 4 test reef kit in large part to monitor my KH. I very early killed my reef because the include KH testing solution is very diluted.

A few days before my kit arrived my local fish store measured a dKH of 9.0
With a goal of 10-11, I added some buffer equal to what it took to go from 8 to 9 dKH. Boy was I surprised when I reached drop 17 and it still hasn't change color at all.
Tested multiple times after a couple of water removals, the lowest read I got was 13 dKH.

The exact same water was actually 8. This was done by using his own store bought API reef kit.

The worst part is that Amazon does not allow returns of this product, and there's no way to swap out this one bottle because there is no 3rd party vendor I'm directed to by Amazon to discuss replacments, nor any person or place to complain to about this faulty equipment (except by writing this review).
------------
Update: I found the place to talk with amazon about this item, and the issue has been resolved because they'll send me a replacement.

So on the one hand you may need to double check the strength of reagenta with a friend's reef kit - but Amazon is actually pretty helpful and generous when you are finally connected to a real person on the phone.

So, -1 star for this bad KH testing batch and the near miss to my tank ecosystem, but that still leaves 4 stars for this kit that is great for the beginner hobbyist.

Good luck!
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3 people found this helpful
Report
Reviewed in the United States on September 12, 2023
Reviewed in the United States on January 8, 2023
Reviewed in the United States on January 17, 2024
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3.0 out of 5 stars Mediocre Test Kit, Not Very Reliable But Good Enough
Reviewed in the United States on January 17, 2024
Test Tube Cracked Easily and doesn't give the best results, every time I test the parameters haven't changed a single bit.
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One person found this helpful
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Reviewed in the United States on March 27, 2019
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5.0 out of 5 stars Not a scientist
Reviewed in the United States on March 27, 2019
But everything seems to be working well. Just be sure to follow instructions ( Does not require you to be a scientist ) soon you will know what to do by habit and be able to just do the test without reading the instructions every time well some of us it took me forever. Good luck and Reef On. I am currently cycling my saltwater but I use API for my four freshwater tanks as well.
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One person found this helpful
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Top reviews from other countries

blandina
5.0 out of 5 stars Gr8 product for reefers. High quality.
Reviewed in India on October 17, 2018
Adii
5.0 out of 5 stars Fast Shipping
Reviewed in Australia on May 6, 2020
Farhan A.
5.0 out of 5 stars Five Stars
Reviewed in India on August 4, 2016
Vikas Dixit
5.0 out of 5 stars Five Stars
Reviewed in India on April 9, 2016
One person found this helpful
Report
Liz Leduc
4.0 out of 5 stars Four Stars
Reviewed in Canada on May 14, 2017