3 of 3 people found the following review helpful
5.0 out of 5 stars
Using Sper-fine filters, 20 Dec. 2012
Makes the water crystal clear. Need to place it on inside of carbon filter adjacent to the white filter for best effect. When the filter bubbles reduce its the super-fine filter is full and needs to be replaced. The frequency of filter change is affected by the type of food, amount and distrubance in the tank. Could not purchase these from my local store so great service from Amazon.