Chemi-Pure Aquarium Filter Media - 5 oz. - 6 pk.
One 5 oz. jar treats up to 20 gallons.
Ratings & Reviews
Chemi-Pure is cheaper.
I use these for all of my tanks now. They get changed once every six months and really save money over using prefilled carbon. I will add floss to the filter to help catch the larger pieces of debris and rinse all of the filter contents once a month in treated water.
<br>The only issue I have had is that the directions say to rinse lightly. If they are not rinsed enough, the tank water turns black.