Aquaria Tech informs you: 

The pH value has a great impact on the growth of corals, calcareous algae and many other biological processes. The pH value should not vary by more than 0.3 units during 24 hours and, preferably, should be kept between 8.0 and 8.2. A too low PH is reflected by low alkalinity and insufficient oxygenation. The Salifert PH Test is accurate enough to monitor PH fluctuations of about 0.2 units.

Sufficient for 50 tests. Ph range 7.4-8.6

Instructions:

1) Fill the supplied container with 5 ml of water 

2) Add 5 drops of reagent and shake for 10 seconds 

3) Look through the side of the container and compare the colours with the colour scale.

We advise you to observe the colours in natural light. 

WARNING: 

Keep out of reach of children. Not edible.