Fine Grade - To be used as a substrate for all Non-fluidised Calcium Reactors
The difference between the two is that the Rowalith C which is the dark media contains more carbon and is slightly harder where as the white Rowalith W is softer and dissolves more quickly.
In a fluidised reactor if it is filled with all W type then it will tend to run cloudy and so we blend it 50:50 with the C to make Rowalith C+
In a non fluidised reactor the softer media is a bonus as it dissolves faster and as it is not being bumped together then it tends not to cloud the water.
If Rowalith C is run by itself then it will take slightly longer to dissolve at the same rate but causes no cloudiness in the reactor.
Both media are excavated from ancient coral beds and therefore contains magnesium in the same levels that you find in the corals