---
product_id: 1627371
title: "API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit"
brand: "api"
price: "R1193"
currency: ZAR
in_stock: true
reviews_count: 13
category: "Api"
url: https://www.desertcart.co.za/products/1627371-api-saltwater-master-test-kit-550-test-saltwater-aquarium-water
store_origin: ZA
region: South Africa
---

# 4 vital saltwater parameters compact 7x5.75x4.75 in kit 550 precise tests API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit

**Brand:** api
**Price:** R1193
**Availability:** ✅ In Stock

## Summary

> 🌟 Keep your saltwater sanctuary flawless—because your fish deserve the best!

## Quick Answers

- **What is this?** API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit by api
- **How much does it cost?** R1193 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/1627371-api-saltwater-master-test-kit-550-test-saltwater-aquarium-water)

## Best For

- api enthusiasts

## Why This Product

- Trusted api brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Protect Your Investment:** Prevent invisible water hazards that stress or kill fish—stay ahead of problems before they start.
- • **Master Your Marine Habitat:** Accurately monitor pH, ammonia, nitrite & nitrate to keep your saltwater aquarium thriving.
- • **Precision Meets Simplicity:** Easy-to-use liquid reagents with color card for reliable, lab-grade results at home.
- • **550 Tests, Endless Confidence:** Bulk testing capacity ensures long-term water quality control without frequent repurchases.
- • **Trusted by Aquarists Worldwide:** Industry-standard kit with 4.7-star rating and decades of proven performance.

## Overview

The API Saltwater Master Test Kit offers 550 precise tests to measure the four critical water parameters—high range pH, ammonia, nitrite, and nitrate—in saltwater aquariums. Designed for weekly monitoring, this compact kit includes six reagent bottles, four test tubes with caps, and a color comparison chart, enabling professional-grade accuracy to prevent harmful water conditions and protect marine life. Trusted by aquarists for nearly 60 years, it’s the essential tool for maintaining a healthy, vibrant saltwater environment.

## Description

Protect marine fish and invertebrates from unsafe water conditions with API SALTWATER MASTER TEST KIT. Fish waste, uneaten food, plant refuse and other organic compounds can create harmful levels of ammonia, nitrite and nitrate as well as cause drastic fluctuations in pH. These unhealthy conditions can result in fish stress, gill and tissue damage and even death. The API SALTWATER MASTER TEST KIT accurately measures these four saltwater parameters that are key to keeping your aquarium healthy. It includes six bottles of liquid test reagent, four test tubes with snap-tight caps, a holding tray and a step-by-step instruction booklet with information on how to correct unsafe water conditions. Simply fill a clean test tube with 5 ml of water, add the appropriate test drops and compare results with the color chart. Then follow the recommendations to modify conditions if action is needed. 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.

Review: The best freshwater basic testing kit... - 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.
Review: Good kit! - Works perfectly was hesitant on spending more rather than getting test strips but I’m glad I invested in this kit way more accurate and comes with good amount!

## Features

- Contains one (1) API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit, including 6 bottles of testing solution, 1 color card 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 saltwater aquariums: high range pH, ammonia, nitrite and nitrate
- Designed for use in saltwater aquariums
- Use for weekly monitoring and when water or fish problems appear

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B001EUE808 |
| ASIN  | B001EUE808 |
| Best Sellers Rank | #1,283 in Pet Supplies ( See Top 100 in Pet Supplies ) #2 in Aquarium Test Kits |
| Brand Name | API |
| Color | No Color |
| Country of Origin | United States |
| Customer Reviews | 4.7 4.7 out of 5 stars (39,587) |
| Date First Available | June 20, 2004 |
| Date First Available  | June 20, 2004 |
| Department | Unisex-Adult |
| Department  | Unisex-Adult |
| Directions | Follow the instructional booklet directions for individual testing of each water parameter, and test weekly for best results. |
| Included Components | API Saltwater Master Test Kit |
| Is Discontinued By Manufacturer  | Yes |
| Item Dimensions LxWxH | 7 x 5.75 x 4.75 inches |
| Item Package Dimensions L x W x H | 6.69 x 5.16 x 4.39 inches |
| Item Weight | 16 ounces |
| Item model number | 401M |
| Item model number  | 401M |
| Manufacturer | Mars Fishcare |
| Manufacturer  | Mars Fishcare |
| Manufacturer recommended age  | 1 month and up |
| Material | Plastic |
| Model Name | SALTWATER MASTER TEST KIT |
| Number of Items | 1 |
| Product Dimensions  | 7 x 5.75 x 4.75 inches; 1 Pounds |
| Size | 1-Pack |
| Style | Saltwater |
| Target Audience Keyword | fish |

## Images

![API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit - Image 1](https://m.media-amazon.com/images/I/71A-PyQBvVL.jpg)
![API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit - Image 2](https://m.media-amazon.com/images/I/71YLLo0X1rL.jpg)
![API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit - Image 3](https://m.media-amazon.com/images/I/4120clwvUbL.jpg)
![API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit - Image 4](https://m.media-amazon.com/images/I/71LUDG3W-JL.jpg)
![API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit - Image 5](https://m.media-amazon.com/images/I/81R8k+qKRyL.jpg)

## Available Options

This product comes in different **Style** options.

## Questions & Answers

**Q: How many tests can be run with this kit?**
A: About 120.   Problem is that if you use the full set of products daily you will quickly  run out of the ammonia test and the Nitrates tests (each with 2 bottles) because they take 8-10 drops each, compared to the Ph test which only takes 3 drops.  I mainly test ammonia and nitrites so I've had to buy separate ammonia kits twice now because I ran out of fluid, while my high range ph bottle is nearly full.    Also - Prime, AmGuard and other products convert Ammonia into harmless Ammonium however, it will still read as ammonia on your API kit - so it's basically lying to you.  There are kits that will show you active ammonia and harmless ammonium and my API kit reads 8.0 ammonia but the other kit reads it as all harmless ammonium and zero active ammonia.  You have do dose your tank with Prime every 48 hours or less to keep the ammonium from converting back to killer ammonia.  This will keep happening until your tank finally converts the ammonium to nitrites.  My 2 of my 4 well-cycled tanks somehow lost their cycling so that's not happening for those tanks yet.

**Q: I'm a newbie. I have a betta in 10G tank and I'm told that I need to test the water always.Not sure if I should get this or get cheaper ones instead.**
A: Frankly, with a 10G tank you should just be doing weekly water changes of at least 25-30%.  You can't really "let things go" with a tank that size and it's unlikely that you would have ammonia spikes with such frequent water changes.  I have a little 5.5 gallon with a couple of albino cory cats and I use a test strip every once in a blue moon, but the water is always fine because I do weekly changes.  Am looking at this kit for my 125 gallon tank, but would bother for a tiny tank.

**Q: Would this kit be a good one for my planted aquarium?**
A: Yes, this is a good general water testing kit, unless you have plants that are very sensitive to water hardness.  This kit does NOT include a water-hardness tester.

**Q: Can any of these tests be used for both saltwater and freshwater? I noticed a lot of the individually packaged tests say they can be used for both.**
A: Api ammonia, nitrite and nitrate test kits can be used for both salt and fresh water aquariums, the liquid solutions are the same for salt and fresh. BUT the color cards that you use to compare your test to are slightly different. I have both fresh water and marine. The first time I bought these kits, I bought for saltwater and freshwater and never threw away the color cards. Now it doesn't matter if I get freshwater or saltwater test kits because I have both freshwater and saltwater cards.

## Customer Reviews

### ⭐⭐⭐⭐⭐ The best freshwater basic testing kit...
*by D***Y on June 7, 2024*

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.

### ⭐⭐⭐⭐⭐ Good kit!
*by A***A on January 28, 2026*

Works perfectly was hesitant on spending more rather than getting test strips but I’m glad I invested in this kit way more accurate and comes with good amount!

### ⭐⭐⭐⭐⭐ Must have saves time and energy
*by D***E on February 17, 2026*

Saves me so many trips to the pet store. Super easy to use, easy to clean. Directions are very clear. A must have for anyone with even 1 tank. It's worth the $, you will use it a LOT before you need to replace the drops. I've had 6 tanks at once over 2 years and still had 1/2 my drops.

## Frequently Bought Together

- API SALTWATER MASTER TEST KIT 550-Test Saltwater Aquarium Water Test Kit
- Instant Ocean Sea Salt 50 Gallons, For Marine Aquariums, Fast Dissolving

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*Product available on Desertcart South Africa*
*Store origin: ZA*
*Last updated: 2026-02-28*