I am new to ponds and koi and built my first pond this summer. It is approx. 2500 gallons which terraces through my back yard. It has a river feeding it which ends with a waterfall. I hand digdug and hand poured the entire pond myself and it is made of concrete. I have 25 different variations of koi as well as goldfish. it requires 4 pumps and three different filters just to keep the water running which can seem like a lot of work Some days. it is heated with a 1500 watt floating heater which seems to keep the water at approximately 56 degrees even now when the temperature is 8 degrees outside.here is a picture while still being built.
here are a few other pictures,
