API Saltwater Master Test Kit

The API Saltwater Master Test Kit covers the four parameters that keep a marine tank out of trouble. API's line is that it protects marine fish and invertebrates from unsafe water conditions, and the liquid reagents give you a reading you can actually trust when something is wrong. Browse all of our water testing.

What It Tests

• High range pH, the range marine tanks actually sit in
• Ammonia, lethal long before a fish looks sick
• Nitrite, the second stage of the cycle
• Nitrate, your running score on husbandry and water changes

Note that this kit uses the high range pH test rather than a standard pH test, because saltwater sits at the top of the scale.

What's in the Box

• Six bottles of liquid test reagent
• Four test tubes with snap-tight caps
• Holding tray
• Step-by-step instruction booklet

How to Use It

• Rinse and fill the tube to the line with tank water, add the drops the booklet specifies, cap and invert.
• Read against the color card in natural light with a white background behind the tube.
• Shake nitrate bottle #2 hard for the full time the booklet calls for, or nitrate reads low.
• Test weekly on an established tank, daily while cycling or after a loss.

Specifications

Pairs Well With

• API Reef Master Test Kit for calcium, KH and phosphate, the parameters this kit does not cover.
• Seachem Prime to detoxify ammonia and nitrite while you fix the cause.
• Browse all of our test kits.

Frequently Asked Questions

Does this test calcium or alkalinity?
No. For calcium, carbonate hardness and phosphate you want the Reef Master Test Kit. This one covers pH, ammonia, nitrite and nitrate.

Why is there no low range pH test?
Saltwater sits high on the pH scale, so API includes the high range test instead.

Can I use my freshwater kit on a reef tank?
The chemistry and the color cards are calibrated differently for marine water. Use the saltwater kit.

Do the reagents expire?
Yes, they carry date codes. If an old kit is giving readings that make no sense, replace it before chasing a phantom problem.