What to use to kill dragonfly nymphs but safe for fry ?

[gregbickal]

I have tons of dragonflys at my place. Last July I set up a tank to hatch out and raise some fry. No sooner than I was finished the dragon-flys were already laying their eggs. Weeks later I caught huge dragonfly nymphs swimming around in there. Im sure they are eating my fry.

Is there anything like Mosiquto dunks or something that I can put in that would be safe for the koi fry ?

Did some searches on the web and people said that DIMILIN might work. Any side effects on developing fry ?

[Maurice]

Dimilin Flo Greg, it will sort anything with an exoskeleton, but don't let it anywhere near a natural water coarse. The environment people do not like it!

E-mail me if you have any problems obtaining some.
If you buy it in liquid form, use 1/2 mil per ton.
Maurice.

[gregbickal]

Is that the same stuff that they sell at AES ? What about the food the fry will be eating like Brine shrimp ? Im guessing it would kill the brine shrimp also ? Infusoria, Skuds, etc ?

I have so many dragonflys around, that just the other day, I found one that molted from an nymph on my indoor settling tank. Nymph must have came in with my filter material in November.

[Maurice]

Greg, I’ve not got the AES catalogue, but it’s the same as used for Anchor worms and fish lice.

Yes it will also take out brine shrimp. You need to get your timing right, treat with dimilin and then do plenty of water changes.

Last year I used it for fish lice, within 24 hours, every one was dead and turned to mush.

Your Brine shrimp are only good for a few hours in fresh water, so I don’t think it will be a real problem.
Seeing your only working on a small scale, why don't you net the ponds to stop the dragon flies getting to your water?
Maurice.

[MikeM]

Greg: Dragonflies in Iowa in February? I haven't seen any dragonflies around here since late November. I guess our Florida-ones get chilled when it is below 80F.

[Tom C]

I was in Brooklyn Iowa a few weeks ago and it was cold as hell. It shocks me that you would have problems with dragonflies this time of the year.

How large of a tank are we talking Greg?

Tom

[luke frisbee]

I know PickleBoy is just asking now so he can have it when needed...and Yep Dimlin...get it from a local source in the "pest Control business if you can. It is CHEAP...unless it has the word "koi" associated with it.
And yeah it will corrupt the brine shrimp...after a day...
And of Course California has it listed as a potential Carcinogen....and I can tell you it tastes like artificial sweetner

[dick benbow]

alright Luke, I'll bite....how long have you been using it as an artificial sweetner.
do mosquitos bite you and then immediately roll over dead? (LOL)

[luke frisbee]

Dick?
You'll bite and mosquitoes bite..... I can put to and too twogether.

But just let's put a warning out there.
"Don't sprinkle it into your pond when you are down wind."

[luke frisbee]

Oh and Dragonfly Centaurs will definitely have an impact on them....

Then again I would think a .22 would be enough gun for most of the nymphs...or do they grow big like the Corn out where you live?