filtration

No, it is not. There are three types of filtration: mechanical, biological, and chemical. Mechanical is removing particulate matter from the water. This will be done by the HOB filter. Biological is what is responsible for removing ammonia from the water (actually converting ammonia, but that is another thread). This will be accomplished partially by the UGF and partially by the HOB. You can never have too much biological filtration, becuase the food supply dictates bacterial numbers. Chemical filtration is the use of carbon or other chemicals to alter the water. I personally don't chemically filter my water, however some people are strong proponents of this. It will require some more research on your part before you decide. Just remember, you can't overfilter your water. Phew! I'm tired now. :thud: Hope this helped. Chris