API Calcium Saltwater Aquarium Test Kit, 1 count

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About This Item

Details

  • Contains 1 API Calcium Test Kit Saltwater Aquarium Water and includes 2 bottles of testing solution and 1 glass test tube with cap.
  • Easy and accurate—simply compare your results with the color chart and follow the included recommendations.
  • Corals, crustaceans, mollusks and some types of encrusting algae need calcium for skeletal growth.
  • This kit uses the titration method to measure calcium levels as low as 20 mg/L.
  • For use in saltwater aquariums only.

Instructions

FAQ

Learn More About API From Our Team of Experts

About API Testing

Testing the Waters

For fish to thrive, their aquarium water must be similar to the water in their natural environment. Poor water quality can cause stress, illness and even the loss of your fish. Important water quality parameters include ammonia, nitrite, nitrate, and pH. These can vary over time, and they are invisible to the eye, which is why it is necessary to test weekly. Choose from a wide range of API testing options like the Freshwater Master Test Kit or 5-in-1 Test Strips to accurately evaluate your water.

Pressed for Time? Just Dip and Read

Simply dip an API test strip into your aquarium, swirl it twice, and then use the color-coded chart to determine if your water is within safe parameters or if adjustments are needed. That’s it! API test strips are available in a 5-in-1 version, which includes testing for pH, nitrite, nitrate, carbonate, and general hardness. Ammonia and pH test strips are also available so you can mix and match according to your needs.

The Scientific Approach

Get professional results from the comfort of your home with API test kits. Measure up to six parameters with API Master Test Kits, or pick and choose from a wide variety of individual test kits. Both types of kits come with test tubes and a laminated, calibrated color card. API test kits allow for numerous tests, making them an inexpensive way to help keep your aquarium water quality in check.

How to Correct Aquarium Water Parameters

Too Much Ammonia?

Ammonia is released into the water through gills, urine, uneaten food and more. API Ammo-Lock detoxifies it instantly.

Inappropriate pH Levels?

Fish require a specific pH level to thrive. Use API pH Down to lower freshwater aquarium water pH to the right level.

Too Much Nitrite?

Use API Quick Start to quickly consume nitrite and help maintain an active biological filter.

Nitrates Too High?

API Nitra-Zorb helps remove nitrate and other toxins that can be harmful to fish and lead to algae growth.

About API

The team at API has a passion for fish and understands the rewards and relaxation fishkeeping can bring. For almost 60 years, they have developed premium products with a focus on proven and effective results. API offers a range of testing kits, water conditioners and nutritionally superior fish foods. They are dedicated to making a better underwater world for the benefit of fish and those who keep them.

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Questions & Answers

2 Customer Questions


How many tests will this kit run? It says 1 count in the description.

Answer by ChewyAug 06, 2019
This test kit is intended for one test.

can this be used in freshwater aquariums to make sure that snails and shrimp ate getting enough calcium?

Answer by ChewyJun 03, 2020
API Calcium Saltwater Aquarium Test Kit is a titration test, so it may be used on fresh water.
4.7
Rated 4.7 out of 5 stars
14 Ratings

6 Customer Reviews



Rated 5 out of 5 stars
By MaryAnnM12 on Jan 9, 2026

Cats love them and help with disgestion

I have one cat that has a hairball issue that can sometimes cause comstipation, and another one that has a sensitive stomach that regurgitates sometimes. These treats

I have one cat that has a hairball issue that can sometimes cause comstipation, and another one that has a sensitive stomach that regurgitates sometimes. These treats help both of them get back to “regular”! I give both about 8 a week and it seems to help a lot. Only when I stop for a frequent time do I see digestive issues again. I do not use a food topper, more like a treat.


Rated 5 out of 5 stars
By Joe on Apr 13, 2025

Good kit

Tried and true works as intended

Tried and true works as intended


Rated 5 out of 5 stars
By Michael66 on Aug 14, 2021

Tool for Reef Tanks

Have begun to create a coral reef tank. Corals use the calcium in the tank water. The more corals the more calcium is being used. This test kit is crucial to monitoring

Have begun to create a coral reef tank. Corals use the calcium in the tank water. The more corals the more calcium is being used. This test kit is crucial to monitoring calcium levels to know when it’s time to add more. Again I’m impressed with your company professionalism and personal touch. Thank you so much


Rated 5 out of 5 stars
By allieazalea on Jun 26, 2020

accurate and easy

Api makes great tests but they need to quality check the caps for the tubes.

Api makes great tests but they need to quality check the caps for the tubes.


Rated 5 out of 5 stars
By jazzpr1 on Jan 16, 2020

Nice and accurate

Ran out and needed a replacement I trust it to be accurate

Ran out and needed a replacement I trust it to be accurate


Rated 5 out of 5 stars
By ballen13 on Aug 2, 2018

Great for replacement TEST

I really appreciate that I can replace any part of my Saltwater testing kits. I have back up kits but love how accurate this test is and easy to use!

I really appreciate that I can replace any part of my Saltwater testing kits. I have back up kits but love how accurate this test is and easy to use!