I help to care for this pond for about 3 years, and I gave several of the fish to my father as gifts for birthday or christmas. The pond is roughly 10'x12' on the straight sides and the arc is somewhat larger then 15' (please dont ask me to do the real math to figure it out), and it's roughly 5' deep from the water surface to the pond bottom. There are probably about a dozen koi, 1 feeder fish that is now 8" long named Squeege(dont ask...), and several shubinkin, and pond comets in it. It is actually alot of work to keep it up but not much more then your average aquarium... it is nice because all the pumps and fitlers are proportionally larger so they can actually be easier to clean at times.