Green water ,daphnia, mosquitoes, and overwintering questions. How do they do it????

[KittenFishMom]

I have some green water in my row boat.  I want to capture it in a 5 gallon transparent jug and start some daphnia in it.  Right now I know there are mosquito larva swimming in the water. I'm guessing that if I cover the jug tightly with window screen and wait for all the adult to emerge and starve to death, it could become mosquito free. Has anyone tried this or have you tried something else that worked? A couple of summers ago, I fed live mosquito larva to a tank of fish and the clouds of indoor mosquitoes that hatched and bit and produced more eggs was unbelievable. I would love to try daphnia as a live feed without turning me into a live food for mosquitoes.

I see videos with large outdoor tubs of daphnia, many overwintering and open to the air for rain water and leaves. No one talks about mosquitoes. How do they avoid them?

Thanks so much, KittenFishMom.

[TOtrees]

What’s your region/climate? Are looking for ways to make this work over the winter outside, or bringing it in?

I have done daphnia buckets outside, and kept them mosquito free with mesh netting. But they don’t get enough food from the sun to be self-feeding, ie any green water gets eaten by the daphnia, so you have to feed with spirulina etc to maintain daphnia at levels that are are useful for fish keepers. To put this another way, you can either have green water, or daphnia, but not both.

Also consider mosquito dunks or mosquito bits. They’re a type of pesticide but the active ingredient is a bacteria that ONLY targets diptera larvae. Even then, it doesn’t actually kill them, it just interferes with their larval development and stops them from reaching the pupal stage. I’ve never tried it in a daphnia culture, but I suspect it would be harmless to them. 

[KittenFishMom]

@TOtrees I'm in central New York. zone 5 I think. Everything freezes outside in February, if not before. I would expect to have daphnia to feed when the sun is low in the sky, but it would be cool to get some this fall and next spring, if the make it through the winter.

 

[TOtrees]

@KittenFishMom i’m just north and west of you outside of Toronto, similar climate zone. Personally, I would make space for daphnia culture inside year round, and if you want, start a second seasonal culture outside during the summer months. 

I’ve been keeping daphnia in a 20 gallon tank in my basement fish room F or around 3 years, maybe more. In that time, I’ve never had a collapse, although the population has had its ups and downs. I keep a separate culture in a 5 gallon bucket as a back up.

Yes, it’s possible to raise daphnia outdoors, and I’m sure there’s some way to keep them over the winter, but when you compare the amount of effort between outdoor and indoor, and the yields that each scenario gives, it just makes way more sense to me to focus on indoors as your staple, and play with outdoors as an experiment if you want and you have time.

I’m guessing your green-water boat situation will freeze solid at some point. Meaning, the only daphnia that will survive through that will be the resting “egg” stage. Come spring, as things thaw, yes, you should expect them to “miraculously” come back on their own, but their numbers will be low and the effort to monitor and sustain them will be relatively high.

Don’t get me wrong, I’m not trying to p00-p00 on your idea. 🙂 I just don’t think the cost vs benefit favours a year-round outdoor process up here. 

[KittenFishMom]

@TOtrees Yes, you are right. I'll wait until my big tank is going again and try to start a colony in one of my many QT tanks. I'm just grasping at straws to try to make summer seem to last a little longer.