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API

API 5-IN-1 TEST STRIPS Freshwater and Saltwater Aquarium Test Strips 100-Count Box

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Availability: Only 1 left in stock, order soon!
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Arrives Saturday, Oct 17
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Size: 100-Count


Style: Aquarium Water Testing


Features

  • Contains one (1) API 5-IN-1 TEST STRIPS Freshwater and Saltwater Aquarium Test Strips 100-Count Box
  • Monitors levels of pH, nitrite, nitrate carbonate and general water hardness in freshwater and saltwater aquariums
  • Dip test strips into aquarium water and check colors for fast and accurate results
  • Helps prevent invisible water problems that can be harmful to fish and cause fish loss
  • Use for weekly monitoring and when water or fish problems appear

Description

Keep your fish healthy and thriving by testing your aquarium water regularly with easy-to-use API 5-in-1 TEST STRIPS. API 5-in-1 TEST STRIPS for freshwater and saltwater aquarium help fish owners measure levels of Nitrite, Nitrate, Carbonate & General Hardness, and pH found in aquarium water. 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 death. Just dip a strip directly into your aquarium and use the color- coded chart to determine if your water is safe, or if adjustments are needed. Then follow the recommendations to treat the water – it’s that simple. 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.

Brand: API


Ph Range: 6.5 - 8.0


Recommended Uses For Product: Freshwater and Saltwater


Unit Count: 1 Count


Manufacturer: Mars Fishcare


Brand Name: API


Manufacturer: Mars Fishcare


UPC: 317163160336 300718524905


Global Trade Identification Number: 36


Item Type Name: Aquarium Test Strips


Item Weight: 1.76 ounces


Model Number: 33P


Part Number: 33P


Unit Count: 1 Count


Number of Items: 1


Material Type: Paper


Sterility Rating: 6.5 - 8.0


Recommended Uses For Product: Freshwater and Saltwater


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Oct 17

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Similar Products

Top Amazon Reviews

    • Affective and easy to use
Size: 25-Count Style: Aquarium Water Testing
Review Image by Elizabeth
The test strips are affective and easy to use. But they do NOT test for ammonia. You have to buy separate test strips for that I suggest The API ammonia test strips they test for both NH3 and NH4. I use them along side these test strips. These test strips test for PH, NO3 (nitrates), NO2 (nitrites), GH (general hardness) KH (carbonate hardness) I use these for my betta tank with tannins because I feel like I can’t get an accurate read with the master fresh water kit with the water being dark. They come in a nice sturdy tube that seals well. Just don’t stick wet fingers in the tube you’ll mess up all your test strips. Just take one swirl in tank a few times and lay flat then follow directions on how to read. It’s easy peasy and very fast I recommend 100% ... show more
Reviewed in the United States on August 14, 2026 by Elizabeth
    • Works good
Size: 4-Count Style: Aquarium Water Testing
Great! I was worried with my fish thinking something was wrong, we could change the water and solve the problem
Reviewed in the United States on August 29, 2026 by Luana Kelly
    • Love these
Size: 100-Count Style: Aquarium Water Testing
I know fish enthusiasts insist you use the water testing kit with tubes and drops... But I've always used these dip stick tests and I swear they tell you what you need to know. Highly recommended. Very easy to use and read the results.
Reviewed in the United States on October 3, 2026 by Devon Mercedes
    • Functional & ez to use
Size: 100-Count Style: Aquarium Water Testing
Easy to use over test kit but unsure how accurate it is
Reviewed in the United States on August 30, 2025 by Gregory Silver
    • API 5-in-1 Test Strips - The Key to Healthy Aquariums
Size: 25-Count Style: Aquarium Water Testing
The API 5-in-1 Test Strips for Freshwater and Saltwater Aquariums have become an indispensable tool in my aquarium maintenance routine, providing accurate and comprehensive testing for crucial water parameters. Here's why these test strips have become my go-to choice for ensuring the well-being of my aquatic friends. The versatility of the 5-in-1 test strips is a standout feature. They cover five essential parameters – pH, nitrite, nitrate, carbonate hardness (KH), and general hardness (GH). This comprehensive testing ensures a holistic view of the aquarium's water quality, empowering aquarium enthusiasts to address potential issues proactively. Ease of use is crucial when it comes to aquarium testing, and these strips deliver on that front. The simple dipping process and quick color-coded results make it accessible for both beginners and experienced hobbyists. The clear and concise instructions included in the packaging further enhance the user-friendly experience. The accuracy of the test results is impressive. The color charts provided are easy to read, allowing for precise interpretation of water parameters. This accuracy is essential for making informed decisions about water changes, adjustments to the aquarium environment, or identifying potential issues that may affect the health of fish and plants. The speed of the testing process is a time-saving feature. Within a matter of seconds, the strips provide a snapshot of the aquarium's water conditions. This efficiency is particularly beneficial for those with multiple aquariums or for regular testing to monitor changes in water parameters. The durability of the test strips ensures reliable performance. The individually sealed strips maintain their effectiveness over time, and the packaging is designed to protect the integrity of the strips until they are ready to be used. This longevity contributes to the overall value of the product. Affordability is a key consideration for aquarium enthusiasts, especially for regular testing. The API 5-in-1 Test Strips offer excellent value for money, providing a cost-effective solution for monitoring water quality without compromising on accuracy or reliability. In conclusion, the API 5-in-1 Test Strips for Freshwater and Saltwater Aquariums have proven to be an essential tool for maintaining a healthy aquatic environment. With versatility, ease of use, accuracy, speed, durability, and affordability, these test strips tick all the boxes for aquarium enthusiasts looking to ensure the well-being of their underwater companions. I highly recommend API 5-in-1 Test Strips for anyone serious about maintaining optimal water conditions in their aquariums. ... show more
Reviewed in the United States on March 5, 2024 by Kyle W.
    • Good
Size: 25-Count Style: Aquarium Water Testing
Good kit, reads accurately and very convenient.
Reviewed in the United States on September 25, 2026 by KT
    • Super easy water monitoring!
Size: 100-Count Style: Aquarium Water Testing
It's definitely important to keep an eye on your fish's health by monitoring them closely, but it can be a little difficult to gauge the water quality just from their behavior alone. Often times when fish start acting strange, it can be too late. That's why these water test strips are so invaluable! You just stick them in the water, swish them twice, and then take them out with the water still on them. Then you can check your water quality by following the color guide on the bottle. The instructions are super easy to understand, and the test strips match the color swatches on the bottle without much deviation so it's easy to read your water conditions. The strips are plastic with little patches on them, so you don't have to worry about them disintegrating while you read them either. (They're durable. Are you happy Amazon suggestions? It just can't read between the lines...) One thing to note is that these strips don't test for ammonia levels in the water, which is a super important thing to monitor too. A little disappointing, but easily fixed by buying a separate ammonia test kit. They aren't quite as reliable as liquid tests, but overall a very useful and easy way to make sure your fish stay happy and healthy! ... show more
Reviewed in the United States on September 1, 2025 by Chloe B.
    • Got a new tank? You're going to want to know about Ammonia, and this won't test that for you.
Size: 100-Count Style: Aquarium Water Testing
These strips are easier to use than the API master test kits, which is why I initially just got them. They also test general and carbonate hardness (GH and KH, respectively), which are important and which those kits don't cover. Finally, these strips are MUCH safer to use - if your child under 12, say, has a tank they're testing it alone most of the time, get both this and the master kit, and make the master kit something you do together - with only you handling the chemicals for Ammonia and Nitrate testing. However... These strips, irritatingly, don't come with instructions. You can google for them, and find a PDF with them on the API website, but after I did that, I found that some of what those instructions say about ideal parameters for tropical fish are really at odds with what I'm reading a lot of other places - especially where hardness is concerned. I think there are even some disagreements with the instructions (which actually are provided, thank goodness) in their own Master Test Kit. Also, the results aren't ideally made for accuracy within the small range of results you're going to be dealing with most of the time. The scale is just too inprecise (like leaving the inches off a yardstick) where you want to know more detail - and that isn't helped by the fact that it's a difficult judgement call which color things have turned too often. The low end of the Nitrite and Nitrate readings, especially, are extremely difficult to distinguish from each other on the basis of tiny differences between very similar shades of pink - and you really, really need to know those results, especially starting up a tank, and you should hope you never see them stray too far from that small range where it is the most difficult to read what's going on with these strips. I trust API's quality to be higher than many of the other test strips out there, but they're still riddled with issues. I can't recommend anyone rely on them alone. ... show more
Reviewed in the United States on February 24, 2022 by S-M Family

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