The tank is a 72 gallon Bow Front. The water side holds 15 gallons of water. There is an overflow built in to keep the water level constant at the height of the land/water divide. The overflow dumps into a home made prefilter box, then into the 15 gallon sump. The sump is fully planted with water plants. A mag drive pump sends the water back up to the tank.
The return water pressure is constant on 4 valves. The first valve directs water through perforated tubing that runs along the back of the tank and into the cave. It helps to flush out any debris that might accumulate. The second valve is for the high waterfall. The third valve is for the lower (left) waterfall. And the forth valve controls a "rain" system over the land side. The rain system makes water changes very easy, I just open the valve and "rain" on the land side. The water on the land side is drained by another valve on the far left of the tank. I drain it directly into a milk jug for disposal.
I, also, use an external Eheim canister filter (just to the left of the sump in the cabinet). It removes water from the tank, via siphon, and fine polishes the water, then returns it directly into the sump.
The entire system is set up on timers and backed up with a UPS system (in case of a power outage).
The water quality is outstanding and both the fish and plants are thriving. If I remove the overflow prefilter fish eggs will drop into the sump and I constantly have baby zebra danios and gourimies.
The sump idea, just kind of evolved as I was setting up the tank. My original idea was to just use an external canister filter to filter the water and run the water features. But it didn't flow enough to filter the water to my liking and didn't allow enough water pressure to operate the way I wanted. I got the idea from the setups used on saltwater reef tanks.
The sump idea then opened up a host of benefits. I could double the amount of water in the tank, there for allowing me to load up the water in the display tank with more fish. Also, I could keep the heaters out of the display tank to keep the set up uncluttered. It also allowed me to keep the water level in the display tank constant by using the overflow tube. With just the external canister, the water level would constantly drop due to evaporation and overflow from the waterfalls; it required constant topping off. It also gave me an enormous capacity for the biological filer.
Then the sump led to even more benefits, when I started to introduce the plants. By setting up the lighting cycle of the sump opposite of the display tank, I was able to provide the aquatic plants with carbon dioxide. The aquatic plants take in carbon dioxide and produce oxygen during the daylight hours, via photosynthesis. The reverse is true at night when no light is present. There for, during the day the sump plants are producing CO2 which is sent to the display tank where those plants take it in and produce O2 which is sent to the sump for use. The plants in the display and sump are thriving and play a big part in removing phosphates, nitrates, nitrites, and ammonia.
When I was researching for my setup, I didn't come across any similar type setups either. But, I wanted a true separation of the land and water areas, not a false bottom setup.
Tim
