Collecting daphnia?

nik_n

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Hello,

Is there a way to collect your won wild daphnia and are there any dangers of doing that? If not how can you get a daphnia culture started.
 
your main risks are 2:
1. dragonfly larvae
2. disease
people will tell you that you can prevent both but you never truly know, and you may not realize it until you find a giant dragonfly larva eating a fish. I would say to buy them but even in my case I have to catch my own so to remove the 2 greatest dangers as much as possible (as I said, never truly safe) you should start your colony at least 2 years before feeding them to your fish since that way the dragonfly larva will get big enough to remove in its majority and for disease, if it looks wrong/sick it probably is wrong/sick but 2 years considering daphnias fast reproduction and short life should be enough to kill the diseased ones, or if you can find one, use an invertebrate safe medicine.
 
your main risks are 2:
1. dragonfly larvae
2. disease
people will tell you that you can prevent both but you never truly know, and you may not realize it until you find a giant dragonfly larva eating a fish. I would say to buy them but even in my case I have to catch my own so to remove the 2 greatest dangers as much as possible (as I said, never truly safe) you should start your colony at least 2 years before feeding them to your fish since that way the dragonfly larva will get big enough to remove in its majority and for disease, if it looks wrong/sick it probably is wrong/sick but 2 years considering daphnias fast reproduction and short life should be enough to kill the diseased ones, or if you can find one, use an invertebrate safe medicine.
I should clarify that your medicine should only be for parasites, NEVER use a bacteria medicine unless you know the exact bacteria strain if you do you risk creating an unkillable super-bug (and we don't want that, do we?)
 
how can you get a daphnia culture started.
you can start by getting a 5-gallon bucket, drill some small holes 5 centimeters under the top of the bucket to work as an overflow, in case you feel like you need it drill another hole for an air line and air pump, and fill it with water, to that water you add some organic matter like cow manure, fish poop from the filter cleaning, dead plants, etc., and wait.
what you are looking for is green dust algae and brown algae and for chlorella and phytoplankton in the water column (aka green water), once that happens you can go catch your daphnia and add it (inspect it first to prevent dragonflies), now your daphnias biggest competitor and your worst nightmare will be mosquitoes so if your bucket has a lid, cut the middle of it just leaving the rim and glue a fine mosquito mesh, that will prevent them from laying their eggs, and the larvae that may have come with your daphnia from biting you once they mature.
this would be the prime time to use your invertebrate safe anti-parasitic medicine, always use it as the manufacturer says, check every week at the bottom of your tank for more dragonfly larvae and remove them.
now if you place your bucket outside make sure it will be in a place where it can get at least 4 hours of sunlight per day, some wind and rain in case it rains, this will cover temperature, algae blooms, oxygenation, and nutrients during the rainy season since rain water contained nitrogen and carbon dioxide which the algae will use to flourish.
every time you do your water changes re-fill the evaporated water from your daphnia colony with the water change water and if you see the water gain visibility then add more organic matter since that means your algae is receding because of a lack of food.
with this, you should be able to breed some daphnia.
 
The following link tells you how to culture green water and daphnia, among other things.

You can collect daphnia from ponds or lakes in spring and early summer. Just drag a net around the shallow water.

When you get the daphnia home, put them in a container of green water. Leave them there for a few weeks. Then take the baby daphnia out and put them into a clean container of water. Wait a month or so and take some of the babies from that culture, to start a new culture. Let them grow for a month and use the daphnia from the last culture to feed your fish. They will be free of diseases.

The first 2 cultures of daphnia can be left to dry out and a few months later you can add some green water to them. The daphnia produce dormant egg sacks that survive drying and hatch when wet.

Start new cultures every few weeks just in case one crashes.

Try to get daphnia from ponds that do not have fish or water birds, and ponds that dry out during summer. They will have fewer disease organisms.
 
Thank you all. Your advice is really helpful. I would definitely like to try to culture "wild caught" daphnia but for now I will most likely get a start up culture from the store and then later in summer, when I have more time I might dedicate some time to starting from scratch. To be honest I didn't think getting wild daphnia would be so complicated, but it seems as a fun project.
 
If you can buy live daphnia from a shop, put some in a container of green water and culture it. They breed rapidly and within a couple of weeks you will have heaps.
 
Hello :)
You should use a brine shrimp net if you want to collect both young and adults. For just adults, use nets with a "suitably looser" weave.
 

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