Silicate is often present in tap water and can occur in purified water if your RO or DI unit is not functioning properly. High levels of silicate cause algae blooms, and prevent your fishes and invertebrates from taking up some essential trace elements. Salifert's Silicate Test Kit is an extremely accurate and precise test for silicates, with bold colors and helpful comparison charts to remove all doubt.
Add 6 drops of the Si-1 liquid reagent and swirl gently for 10 seconds.
Add 2 drops of Si-2 liquid reagent and swirl the contents gently for 10 seconds. Allow to stand for 5 minutes.
Add 4 additional drops of Si-2 reagent and swirl the contents gently for 10 seconds.
Add to this 1 level scoop of Si-3 and swirl the test vial for 20 seconds.
Look through the side of the test vial while holding the white part of the color chart firmly against the other side.
Use diffuse daylight when comparing colors. An intermediate color corresponds to an intermediate dissolved silicon content.
The silicate values are in ppm (mg/L) silicon oxide.
If the value is higher than 1 or so ppm, extend the range by placing the test vial a white part of the chart and comparing the colors by looking from above. Multiply the color chart value by 5, extending the range from the initial 3ppm to 15 ppm.
Avoid using tap or RO water which contains more than 2 ppm as dissolved silicon.
In marine water the dissolved silicon content should be below the detection limit of this test.