Filtration - We started with a Penguin 330 Bio Wheel and a powerhead running an Undergravel filter.  This seemed to work well at first, but we soon found Nitrate levels going through the roof!  The culprit?  The Undergravel filter.  Upon removal of the Undergravel filter (not fun!), I went to a sump setup.  Using a 10 gallon aquarium, I built my own DIY Wet/Dry Filter System.  Placing the Sump underneath the aquarium, I purchased a Pre-Filter box at my Local Fish Store (LFS).  This Pre-Filter box does several things - it skims water from the surface of the tank - where protein wastes accumulate.  It also maintains the water level in the tank.  Of course, it has a sponge filter that "pre-filters" the water before sending it down to the sump via gravity. Here I built a simple pipe system out of PVC pipe.  It has 2 Ball Valves for redirecting water.  At water change time, I simply open one valve, and close the other, and water drains into a bucket!  The fish are never disturbed!  Once at the sump, the water enters an acrylic box that I fabricated at a friend's plastic shop.  It has a layer of filter material, then 2 gallons of Bio-Balls for biological filtration.  I later removed this box as well, for it was also a "Nitrate Factory" in disguise!  Water then enters the sump, where approximately 7-8 gallons of water are contained.  The larger the sump, the better!   The sump contains a heater, a skimmer and an AquaClear 802 powerhead used to pump the water back to the aquarium.  I also built a baffle that forces the water to go through a layer of crushed coral.  Over time, this crushed coral layer has developed into a "live filter" of many different organisms - small feather dusters, tiny shrimp-like creatures (copepods), worms and others.  The powerhead sends water to a small PVC tube at the top left of the aquarium that runs the depth of the top of the tank, distributing the filtered water evenly across the surface at one end.