My name is Barret. I'm the new assistant manager at a mini-golf course. We have two separate pond systems. Each consists of two concrete ponds connected by a narrow concrete river, with a waterfall at the top pond in each system. They are each something like 15,000-25,000 gallons (sorry I'm not more specific, the plans have been lost for years). The old managers never took care of the ponds, just let them get full of poorly patched cracks and cleaned them out when they started to smell (once every month or two). I intend to fix these up and fill them with plants and fish to keep them looking great through the entire season; these are really spectacular systems with serious potential. I have been keeping aquariums for 10 years or so, but am new to ponds.