here is another version i found:
This pH test can only be used with marine water.
1. Add with the syringe 5 ml of water in the test tube.
2. To this drop with the dropping bottle 4 drops and swirl gently for 10 seconds.
3. Put the open test tube on the white part of the color chart. View from above and read the corresponding pH value. It might be possible that the color is in between two different ones, then the pH value is as well in between the two corresponding values.
Keep out of reach of children.