Mosquito Fish - pro & con?

[Steve J. Noll]

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

[Chad]

I added 4 to my pond in June. Between June and August the mosquito fish
(MF) population exploded. I would estimate it to be over 500--probably
more like 1000 in my 1350 gallon pond. For the past couple months I
believe the MF has pretty much balanced as far as I can tell. I have 6
koi (only 1 old enough to spawn), 2 dumb goldfish(rescued/donated to
pond - born pregnant) and 2 comets (old enough to breed). Well, the
mosquito fish try to eat anything... and are pretty successful with
things under 1/4 of an inch. This includes fish eggs and baby fish. As
a matter of fact, when the mother mosquito fish are giving live birth
they are followed around by other hungry fish awaiting a new meal/birth.

My pond is lined with rock (10 - 40 lbs each) and has alot of plants so
there are lots of hiding places for baby fish. This helped my mosquito
fish population grow. As for other pond fish, I have maybe 10 pond
mutts that have survived the egg stage and hid long enough to not get
eaten while small. From what I can tell, the ones I see are from at
least two different breeding sessions given there sizes.

If I had it to do over, I would. Yeah, there are a lot of fish... but
they are fun to watch swarm around the pond and you see fish every where.

Chad

[~ jan JJsPond.us]

On Thu, 23 Oct 2003 13:43:22 GMT, (Steve J.
Noll) wrote:

>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?

The downside is an upside for you, eating fish eggs. I had them for many
years in my ponds, but they slowly died out. Since they are surface
dwellers I think when I switched to a slow circulation to keep an opening
in the ice, it did them in. ~ jan
See my ponds thru the seasons and/or my filter design:
http://users.owt.com/jjspond/

~Keep 'em Defrosted~
Tri-Cities, WA Zone 7a
To e-mail see website

[Just Me \Koi\]

I wished I never had them in my pond here in Southern California. They
breed and breed. They are everywhere!

I guess they must do a spectacular job with Mosquito control since I have no
mosquito problems.

Do Koi eat mosquito eggs and larvae?

--
_______________________________________
"The difference between 'involvement' and 'commitment' is
like an eggs-and-ham breakfast:
The chicken was 'involved' - the pig was 'committed'."

http://community.webshots.com/user/godwino

"Steve J. Noll" > wrote in message
...
> 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

[~ jan JJsPond.us]

>Do Koi eat mosquito eggs and larvae?

Yes, but larvae can hide out in areas where bigger koi can't get to them.
If you've got good flow throughout your pond, no problem. Skimmers will do
them in also. ~ jan



See my ponds thru the seasons and/or my filter design:
http://users.owt.com/jjspond/

~Keep 'em Defrosted~
Tri-Cities, WA Zone 7a
To e-mail see website