API Master Reef Test

This reef test kit lets you keep track of the water conditions your corals and invertebrates rely on. It checks four parameters that matter most for coral growth and overall reef health: calcium, carbonate hardness (KH), phosphate and nitrate. Regular testing helps you pick up water problems you can't see before they affect your tank.

It suits reef keepers who want to monitor coral-focused chemistry each week. It's a different kit from the saltwater master kit, which covers ammonia, high range pH, nitrite and nitrate. The reef kit targets calcium, KH, phosphate and nitrate instead.

In the box you'll find four glass test tubes with snap-tight caps and a step-by-step instruction booklet with a colour chart. Everything packs into a reusable storage tub. To use it, follow the guide, compare your results against the colour chart, and adjust your water parameters as needed.

For reliable results, shake the reagent bottles vigorously as directed. Mix the test tubes by gently inverting them back and forth every one to two seconds so they don't leak. Rinse the tubes with water straight after each use and avoid soap, which can leave a harmful residue. If staining builds up, a small bottle brush will help.