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Discussion Starter #1
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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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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Discussion Starter #3
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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Discussion Starter #5
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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Discussion Starter #6
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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Discussion Starter #7
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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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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Discussion Starter #9
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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Discussion Starter #10
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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Discussion Starter #11
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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Discussion Starter #12 (Edited)
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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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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Discussion Starter #14
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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Discussion Starter #15
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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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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Discussion Starter #17 (Edited)
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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Discussion Starter #18
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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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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Discussion Starter #20
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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