I'm thinking about adding some Mosquito Fish (Gambusia affinis) to my
Koi pond for two reasons: to control the Koi population - I've heard
they will eat fish eggs - my pond is near it's capacity... and to
hopefully control the population of some very tiny caterpillars living
on the bottoms of my water lily leaves. I've had limited success
controlling the caterpillars with Bti & Btk and they are too small for
the Koi to see & eat.

What are the downsides to adding Mosquito Fish?

Thanks,

Steve J. Noll | Ventura California
| Glass Block Pond http://www.kissingfrogs.tv