# Live Daphnia from frozen Daphnia?



## mistergreen (Mar 3, 2007)

I heard somebody on youtube saying you can get live daphnia from the frozen daphnia cubes you feed your fish. I guess the thinking is some daphnia eggs might be in with the daphnia and those can survive being frozen.
Well I'm testing that theory out. You can't beat 'free' daphnia.

Has anybody done this?


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## Gerald (Mar 24, 2008)

I've never tried that, but if they were in ephippia-making mode when they were frozen, it's certainly possible. They make ephippia at the end of their growing season or when overcrowded, such as when a vernal pool is shrinking.


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## mistergreen (Mar 3, 2007)

I read eggs don't hatch till 5 days to 2 weeks. It's a long wait.
There are 1 to multiple eggs in an ephippia depending on the species. Sometimes the eggs are duds too.


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## Gerald (Mar 24, 2008)

Go find a good floodplain pool without fish, if you want free daphnia.


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## mistergreen (Mar 3, 2007)

None around me that has daphnia that I know of. I'll end up buying some off aquabid. I'm curious about this more than anything.


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## mistergreen (Mar 3, 2007)

Speaking of vernal pools, I'm surprised raising freshwater fairy shrimps isn't more common. I wonder if there are species that don't require a dormant stage and reproduce in good conditions.


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## mistergreen (Mar 3, 2007)

I bought daphnia eggs for fun. Shipping eggs is a lot easier than live. I hear hatching them in distilled water first is the way to go.


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## Gerald (Mar 24, 2008)

Fairy shrimp can reproduce both ways: live-born young and resting eggs, similar to brine shrimp and daphnia. But its tricky to keep a culture going long-term; they usually crash eventually and you need to restart by drying and re-wetting the sediment, and hoping there's some good eggs in it.


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## mistergreen (Mar 3, 2007)

It had been 6 days since I put in frozen daphnia. No babies appeared. Now we know.

I'm hatching new daphnia eggs right now instead. They should hatch in 3 days. I'm using florescent light instead of the recommended sun.


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## mistergreen (Mar 3, 2007)

It has been 2 days and I saw the first daphnia. I guess I should start feeding but in very small amounts. I'm planning to feed yeast and spirulina powder.


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## mistergreen (Mar 3, 2007)

All the daphnia hatched and growing. After acclimating them to my tap water params, minus the chlorine of course, they went into a 10G plastic tub. If all goes well they should reproduce/replicate x10 every week.

I use a dual stage carbon filter to remove chlorine for my fishes and now for the daphnia. Usually people use aged tank water. Chlorine and dechlorinators will kill them off.


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## mistergreen (Mar 3, 2007)

I recommend anybody that keep fish or plan to breed fish to raise daphnia. They're so easy. 

I started with ~50 D. pulex, now I have hundreds and will reach thousands soon. I raise them in the basement where temperatures are stable (72F) in a 10G tub. I feed yeast and spirulina powder where the water is hazy. Their nutrition is relatively the same but yeast has more protein and spirulina has more iron and a few other vitamins. I cover my bases by feeding both. I don't depend on green water so I don't need to waste energy having the lights on 24/7.


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## Gerald (Mar 24, 2008)

Daphnia are "so easy" IF you keep multiple cultures going and keep thinning them out. It's easy for them to get TOO dense rather quickly and then crash.


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## mistergreen (Mar 3, 2007)

Yup, it's not hard to thin them out. I have multiple tanks and a pond.

I've kept daphnia before and had it crashed from excel laced tank water change. I have my water situation worked out and things should be fine. I should keep a spare culture in a liter soda bottle though, in case.


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## mistergreen (Mar 3, 2007)

Oh, when the daphnia 'crash' happens. There's going to be daphnia eggs in the container, probably. I should have revived them instead of scrapping the whole container.


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## Gerald (Mar 24, 2008)

mistergreen said:


> Oh, when the daphnia 'crash' happens. There's going to be daphnia eggs in the container, probably. I should have revived them instead of scrapping the whole container.


Maybe. If it's an end-of-season fall-winter decline when the Daphnia are expecting it, then hopefully there will be viable ephippia (resting cysts). But if they crash during a spring or summer rapid-growth phase due to overpopulation and sudden oxygen depletion, you may have nothing to salvage. They dont always make ephippia. My strategy is to give them away to as many local friends as possible so I can get a re-start culture when needed.


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## mistergreen (Mar 3, 2007)

So, my daphnia tub crashed a month ago. I noticed the daphnia would group together on the bottom of the tub. They developed white spots on their backs which were ephippia. Also, the ephippia floated to the sides of the tub. I think I fed them too much (every day) even though I made it a point to only make the water hazy with the food, not cloudy. So a month later, the snails cleaned up the tub and the daphnia have return with me doing nothing.

I've heard from a guy on youtube that fed yeast and spirulina crashed his culture as well. I'm curious to what the issue is. I know yeast are living and can consume oxygen but there are no sugars around so they can't reproduce. And Spirulina is cultured in high pH waters so I wonder if that would affect the water params. The spirulina would grow in the tub as well....

So this time around, I'll only feed yeast and only once every couple of days.


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## mistergreen (Mar 3, 2007)

I had another crash and I left the tub alone. This time green water developed. I then pipette the eggs off the sides, into the water. They love green water, much more than any thing you can feed them. I noticed the population grew much faster. They've eaten all of the green water within a few weeks and I'm feeding them again.


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## tiger15 (Apr 9, 2017)

I started my daphnia culture in outdoor planters a few years ago, and continue to harvest daphnia year after year. I top the planters with WC water, never clean them, and let them over winter. I mount a window screen over to prevent mosquito from laying eggs. The planters are exposed to direct sunlight for most afternoon, so the summer temp can hit 90s in mid day, and the production drops, but never crashed. The most productive time is spring and fall. Certain time of the year I saw a lot of floating black pepper seeds, and I guess they must be ephippia, but I am not certain not knowing what they should look like. It’s care free life food.


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## mistergreen (Mar 3, 2007)

Yeah, I find growing daphnia indoor easy too. I'll try a batch outside. I found a secret to growing green water. It just needs a dash of micronutrients.

The ephippia's color will depend on the species. Mine are white specs.


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## tiger15 (Apr 9, 2017)

Outdoor is easier than indoor as it needs no care other than topping or replacing with nutrient rich WC water. Sunlight drives green water to feed daphnia. Indoor cultures need to be fed with yeast regularly. But outdoor production is inconsistent subject to nature and bloom and bust cycles.


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## mistergreen (Mar 3, 2007)

I don't even do water changes. The yeast,spirulina, and snail poop seems to be enough. I do add a little coral in the tub to stabilize pH and calcium.


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## mistergreen (Mar 3, 2007)

I added a pinch of protein powder in the yeast, spirulina mix. I only had whey protein around or I would have used soy protein. I make sure to not over use it because protein spoils easily. I think protein is a macro nutrient for these guys. They seem to produce a lot more babies.

I read this on caudata.org.


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## mistergreen (Mar 3, 2007)

I've added a handful of dried leaves and it seems pretty good for the population.


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## mistergreen (Mar 3, 2007)

My daphnia crashed and covered with maybe BGA. I added more snails to eat the BGA. Thankfully green water has taken over since the BGA is reduced.

I couldn't figure out why the daphnia haven't returned. They always have. I measure the pH is it's 8.8pH. Quite high from algae actions? I added a tablespoon of vinegar to bring it down to 7.0. If this doesn't work, I'll need to buy a new culture. Maybe try my hand with moina.


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## mistergreen (Mar 3, 2007)

I ordered moina off ebay. I went ahead and added a heater to the tub since moina preferred 75f-80f. I also threw in a handful of alfalfa hay which should be food for all sorts of critters.

I pulled out my microscope to see what's in the green water. It's chlorella sp. and some tubular diatom.


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## mistergreen (Mar 3, 2007)

I received the moina and floated the bag in my container to temperature acclimate. It seems they're really sensitive to parameter change. Quite a few died in the bag just from the temperature acclimation. I cut 2 holes in the bag for the water params can acclimate. I released them after an hour. They seemed fine at the time but I didn't see much the next day. My tub is full of green water so it's have to see.

I assumed the majority of them died off. I saw only few a few now swimming by the light so hopefully those few can breed up a storm.


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## mistergreen (Mar 3, 2007)

Good news, The green water is clearing up now I can see I have moina AND pulex. I guess the pulex from the previous batches didn't completely die off.


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## mistergreen (Mar 3, 2007)

The density on moina is incredible. The babies which out numbers the adults like 30:1. They're also baby brine shrimp size. This looks like a good replacement for BBS.

When collecting the moina, I've changed my method by siphoning them out with along with 1-2 gallons so I'm doing water changes also which helps to keep the population stable. I harvest 1-2 times a week.


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## mistergreen (Mar 3, 2007)

I had to move tanks around and the stress wiped out the moina & daphnia. I have this little container of moina that I can reseed the bigger tanks.

But for some reason, the daphnia won't take. After a month of not taking, I did big water changes and still nothing. I then added a little crush coral and it worked. I guess it raised and stabilize the pH in addition to adding extra kH & calcium. I guess that's the secret for my water parameter. Out of the tap, my water is 7.6pH, 4dkH, 4GH.


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## mistergreen (Mar 3, 2007)

My daphnia have produced ephippia. Not sure which species though. I have 3 species in the tank; pulex, monia, and clinging daphnia. Either way, I need to harvest to reduce the stress.


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## Noahlikesfish (Apr 17, 2021)

How do you get daphnia from nature? I’m starting to go on an escapade in my pond to make a naturalistic ecosystem in my aquariums. I found fry in some dead hornwort from my 40g I was using to make mulm from. It shows how adaptable life is in aquaria and even though you can’t see it at 1st there is always microfauna and little things in aquaria. And I want to make this happen to the extreme in my 10g and 40g


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## mistergreen (Mar 3, 2007)

You can find daphnia in vernal pools where fish don't live. Fish will eat any daphnia in the pool or tank so having them living in your fish tank is not feasible. Also, you have to feed them microalgae or yeast.


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## Noahlikesfish (Apr 17, 2021)

Oh ok. So just look for the dirtiest puddles? B/c the pond where i live has fish. Will I still find like copepods and scuds? I want to make a natural food culture and honestly anything can work as food right?


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## mistergreen (Mar 3, 2007)

Finding a fishless pool is good for finding parasite-free live food also. Parasites need the fish as the end stage of their cycle and crustaceans & snails as the carrier/vector.
You need to understand what your live food eats. Daphnia eat floating microalgae, yeast, bacteria. Scuds will eat vegetation, detritus, and you can find them under leaf little in the mud. You might be able to find tubifex worms too.

Some people find it easier to raise daphnia in a bucket outside. The sun will generate green water for the daphnia to eat but the heat of the summer & winter will also crash the population. They will come back when the environment is suitable. See the picture of the eggs (ephippia) they produce that I posted.


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