andedammen is correct in that Koi will eat FA, and he's also correct that they will eat it as a last resort. In a Koi pond, there typically isn't a dirt bottom, so they cannot root in the pond bottom for invertebrates, etc.

Personally I would not put Koi or Carp in my pond, I'd rather adjust the amount of light penetration in the water via fertilization and photoplankton bloom vs. stirred up sediment from bottom feeding carp.


www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).