Pond Boss Forums MANAGING AN EXISTING POND Evaluating and adjusting fish populations Grass Carp, Does this make any sense ?

Tilapia and GC are my preferred biological control for FA and water primmrose - don't know anything about DW.
GC on a flyrod is a blast and you can catch them on pellet flies when you want to remove them.

GC will will eat water primrose if that's all they have to eat, and if trained will continue to eat it after more tasty stuff comes along.

Goats are the answer to water primrose however - as ewest says, "they will wrap their lips around the stuff and pull it out of the pond". They love the stuff.
Works for me.