IF I HAVE A 12 X 6 FT POND THAT IS 2 FT DEEP. WHAT SIZE POND PUMP DO I NEED?
ALSO IF I'M GOING TO HAVE KOI FISH, FOUNTAIN AND WATERFALL WITH THE 12X6 FT POND WOULD I NEED A PUMP FOR FOUNTAIN AND PUMP FOR POND?
I would use at least a 3500 gph pump with a bio filter. I would probably buy a smaller pump for the fountain....maybe 450gph depending on the height of the fountain.
Koi like a deeper pond than 2', so consider that in your digging. You might want to stick with goldfish. Having koi means massive filtration systems and lots of maintenance.