So my father has a 3000 gallon Koi pond and he wants to unload some of his fish. Is there any negative effect if I take say 4 of them for my pond? I'm thinking I probably dont want them for the same reasons I wouldn't want carp. I would have a heck of a time getting rid of them when they get really big and stir up my water.

I have SMB, BG, PSeeds, and Redbreast in my pond currently. Forage is in there as well - FHM, Crayfish, Grass shrimp, Snails, Freshwater clams, etc.

I had a decent amount of FA growth this summer as well as a very large amount of both Arrowhead and Widgeon Grass.

I'm still really new to the pond thing and I wouldn't have even considered these if they weren't going to be free.