Mosquito Fish: Pro or Con?

[Donna Saverino MI]

I'm thinking about adding mosquito fish. But I hear they can reck havoc. So, I thought if I just buy one, they can't mass produce. Any Comments?

 

[Mmathis]

Are you asking as a mosquito deterrent? Do you have goldfish or koi, as those will eat any mosquito larvae that end up in the pond. Now, if you have a good and active water flow (water movement) through the pond, you probably won’t have a problem with mosquitoes as they will lay their eggs in still water, not moving water.

 

[Donna Saverino MI]

Are you asking as a mosquito deterrent? Do you have goldfish or koi, as those will eat any mosquito larvae that end up in the pond. Now, if you have a good and active water flow (water movement) through the pond, you probably won’t have a problem with mosquitoes as they will lay their eggs in still water, not moving water.

I have some areas that have quiet water and can produce larva. I use the Dunks to help and just keeping an eye for any wigglers. But I'm sure some get pass me. That's why I am thinking about the fish and want someone that has them to comment on them before I buy one or two.

 

[Lisak1]

I've never had them, but I've read stories about people who added them and regretted it as you can never get rid of them. One story I read the owner emptied the pond and let it sit for weeks, hoping to kill them all off. When he refilled it, there they were. They had some how managed to survive in the plumbing of the pond where he couldn't get to them.

As @Mmathis goldfish will do the same thing in a pond. I wish I could find an old thread here when @Meyer Jordan commented about mosquito fish. Hang on - let me search!

 

[Lisak1]

Here it is. @Meyer Jordan posted this when the question came up about the value of adding gambusia to a pond:

Although the use of Gambusia (Mosquito fish) has been touted by many to be a good specie for the control of mosquito larvae, the facts do little to support this claim. In truth, common Goldfish and even Koi offer more complete control as they are able to prey on the largest of mosquito larvae. Add to this the fact that Gambusia much prefer dining on the zooplankton in a body of water, the eggs and larvae of other fish and even their own young actually imparts more negativity to the impact that they have on an aquatic environment. Often in ponds that have a large population of Gambusia (there is no other size due to their rapid rate of reproduction), Green Water conditions are more likely to occur and be more severe because of the absence of the zooplankton that utilize algae as food.
These two (2) links will provide the complete factual picture of these most troublesome fish.

http://www.gambusia.net/

https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=846

 

[Sisha]

I'm thinking about adding mosquito fish. But I hear they can reck havoc. So, I thought if I just buy one, they can't mass produce. Any Comments?

Don't do it!!!!!!!!!!! They are illegal to sell, buy or transport here in South Australia. A government report by the CSIRO discovered that when fed a diet of mosquito larvae they eventually died. The fish prefer tadpoles, eggs, other small fish. They will nip little pieces from larger fish causing wounds that get infected, in large numbers they will eat a large sick fish alive. At the rate that they breed, they can decimate a pond very quickly. Healthy fish can survive the constant attack though but I wouldn't want them to. Stick to Goldfish, Shubunkins and Koi, it's the reason I built my first pond over 30 years ago, to get rid of mosquitos.

 

[Nevermore44]

Down in Ohio here.... I've had mosquito fish in my pond for 10 years straight without any apparent issues. I got them from my father who had some in his pond. I don't have any standing water areas of the pond except for (formerly) several marginals in baskets near the edge. They seem to stay in groups poking around every inch of the pond. I haven't seen them mess with my goldfish or koi. So don't know if it's from the fish or just my pond conditions... but I don't have any mosquito issues.

In regards to goldfish and koi eating mosquito larva... maybe it happens when they are very small... but I would think once you fish get to a decent size (3-4") and you are feeding them on a routine basis... they aren't looking for mosquito larva anymore. I say this because the mosquito fish of all ages ... from tiny ones smaller then a grain of rice... to larger adults... will swim all around the goldfish and koi without any issues. My fish just don't care about them at all... so I would then assume they don't care about even smaller mosquito larva.

Their numbers grow through the season like guppies do (nothing crazy)... but then once winter roles through and the pond freezes up several times... their numbers are cut way back by spring. So maybe population control would be an issue in a warmer climate to me. I see no negative to them in my conditions.

 

[Mmathis]

Again, folks.....remember that mosquitoes don’t lay eggs (as a general rule) in moving water. They prefer standing, still water that comes from pots and other containers that fill with rain water or water from watering the lawn. So, maybe a tank you have set aside as a plant-grow area — without a pump and no aeration might attract mosquitoes, but rarely will they choose the waters of a moving pond to lay their eggs.

And as to whether the m-fish, koi, gf actually eat the eggs and/or larvae........ How many of you with an active pond have actually seen a mosquito raft or floating larvae in your pond? I never have.....but find them all the time in my “mosquito farms” — you know, those water traps you have to flip over all the time. And Louisiana is one of many states that share the title of Mosquito Capital, sooooo.

When I was going through my fry-raising stage, I searched for larvae to feed the babies, and just for fun would “treat” the pond fish. The larvae never stood a chance!

And I do seem to recall that the OP clarified that she was looking for something to protect a “quiet area” (post #3 above).

 

[Lisak1]

How many of you with an active pond have actually seen a mosquito raft or floating larvae in your pond?

Never. The only time we saw mosquito larvae was when we were building the pond and rainwater would fill up small pools in the liner we had draped everywhere. They will find every bit of standing water, that's for sure!

Our mosquito problem was greatly reduced when we put in the pond - don't know if that was the fish, frogs, dragonflies, etc eating them or if it's because we no longer have grass in the backyard so they have nowhere to hide and wait for us to arrive in time for dinner! Don't get me wrong - we still have mosquitoes, but no where near what we did pre-pond.

 

[Nevermore44]

Ditto.
Also as a mosquito aside.... to help keep you population down... they say you should actually keep a tray of water off to the side that has been treated with BT. So it's basically a trap to keep them at bay vs laying eggs elsewhere.

 

[Sisha]

Down in Ohio here.... I've had mosquito fish in my pond for 10 years straight without any apparent issues. I got them from my father who had some in his pond. I don't have any standing water areas of the pond except for (formerly) several marginals in baskets near the edge. They seem to stay in groups poking around every inch of the pond. I haven't seen them mess with my goldfish or koi. So don't know if it's from the fish or just my pond conditions... but I don't have any mosquito issues.

In regards to goldfish and koi eating mosquito larva... maybe it happens when they are very small... but I would think once you fish get to a decent size (3-4") and you are feeding them on a routine basis... they aren't looking for mosquito larva anymore. I say this because the mosquito fish of all ages ... from tiny ones smaller then a grain of rice... to larger adults... will swim all around the goldfish and koi without any issues. My fish just don't care about them at all... so I would then assume they don't care about even smaller mosquito larva.

Their numbers grow through the season like guppies do (nothing crazy)... but then once winter roles through and the pond freezes up several times... their numbers are cut way back by spring. So maybe population control would be an issue in a warmer climate to me. I see no negative to them in my conditions.

Your'e lucky then, I don't have the luxury of my pond freezing to knock the buggers off. I feed my fish all year round. The frogs take care of them in the dam. One year I noticed larvae in the pool which made me realise the chlorinator had died so I know they are around. I've read of many having issues with these fish, even on this site so why tempt fate, I'd stick to the fish that live harmoniously together.

 

[Nevermore44]

wow... so i did some reading up on these guys. I wouldn't put them in the pond at this point. Though they are quite benign for me.

 

[Donna Saverino MI]

I read somewhere to place a pan of water with a little soap so the B--ch will drown trying to lay her eggs. So I have one in between some plants. Drown B---ch! I HATE mosquitos

 

[LarryM]

I've had mosquito fish in my ponds as long as I can remember. Never had a problem with them. My wife thinks they are cute. The population goes up and down through the year. I expect their numbers to go down dramatically next year because I will be adding a couple dozen Ozark Longear Sunfish next year as a predator element to control the population when the goldfish and koi breed. We'll see how the mosquito fish do with sunfish in the pond.

 

[Sammy43]

I'm thinking about adding mosquito fish. But I hear they can reck havoc. So, I thought if I just buy one, they can't mass produce. Any Comments?