Daphnia

[Mugwump]

..saw this over on 'Aquaboards'.....interesting......Bill?..Dennis?....comments?

...............
......Might not be very useful, but interesting. Had some small Spectrolebias fry in a sandwich container with some green water and the small fauna that come with it. Some wasn't so small though, and there were some Daphnia magna in there too. I left them alone and after a few days added some newly hatched BBS. As I figured, most of the fry were able to take, one, maybe two BBS. These are really small fry. I left it for a few hours then went back to pipette out the leftover BBS.

Surprise! No leftover BBS, but some newly orange, fat daphnia. Yup, the daphnia were loaded up on BBS. Never saw or heard of this before, so I did an experiment. I netted a flock of daphnia and put them in a petri dish with a squirt of new BBS. Seems they take them on the hoof and after they fall to the bottom. The BBS diminished, and I left it overnight. By morning, there wasn't a single one left in the dish.

It is therefore possible to make an aquatic version of a Turducken, though I doubt it would be very practical. What I have learned from this as well though, is that daphnia make really good nursemaids for small fry, cleaning up a lot of leftover very fine food, and as the fry grow, the newly dropped very small young of the daphnia provide a great secondary food source.

[BallAquatics]

Daphnia are primarily filter feeders.  I find it very unlikely that they can take in particles as big as newly hatched brine shrimp.  If they could, they would also filter their own young from the water and be extremely difficult to culture.....

Dennis

[Mugwump]

Daphnia are primarily filter feeders.  I find it very unlikely that they can take in particles as big as newly hatched brine shrimp.  If they could, they would also filter their own young from the water and be extremely difficult to culture.....

Dennis

Any idea for a reason to what he's seeing happening..??

[BillT]

Don't know.

Daphnia magna are huge (compared to baby brine shrimp). It seems possible to me.

I have also read accounts of Daphnia and mosquito larvae competing in some way for success in cultures. According to these people, they could eat each other at various ages.

Many species (but not all fish) have evolved behaviors that prevent attacks on the same species, so that may or may not prevent the problems Dennis mentioned. They could possibly due this based on taste, but I have no idea if they do that.

Baby brain shrimp are also filter feeders when they start feeding (at a later stage of development).
If the Daphnia can eat the baby Brine Shrimp, then it might be possible to first gut load the BS and then feed them to the Daphnia to gut load them with the gut loaded brine shrimp,
resulting in Gut Loading Squared Daphnia.

[LizStreithorst]

I would appreciate it if one of you gentlemen could actually test this.  I can't do it because even though I moved my daphnia to inside the house and put their tanks on the bathroom floor, my house got too hot for them survive.  I don't mind reasonable heat.  My house is 80 during the day and 77 when I go to bed.  Most folks like it colder but not me.

Dennis, dear.  I'll be in touch to buy another when it gets cool enough for me to keep them alive.

[BallAquatics]

Dennis, dear.  I'll be in touch to buy another when it gets cool enough for me to keep them alive.

You and me both, way too hot here.  I know the daphnia are long gone,  I may be able to salvage some monia, but the jury is still out.....

Dennis

[BillT]

I could kinda try to with some Moina. I don't have any Daphnia. Many of my fish tend to be small sized species.

Moina are much smaller than Daphnia magna. Their babies are smaller than baby brine shrimp.

Lately, I have been using decapsulated brine shrimp eggs from really low quality eggs (poor hatch rate).
These are more nutritious to the fish (if they get eaten) because there are no developing embryos using up the nutritional energy before the fish eat them.

I'll try some of these in a petrie dish. The size different between the Dapnia and Moina and the unhatched nature of the brine shrimp might mess it up but they may eat the eggs.

Sounds fun.

[BallAquatics]

I'll try some of these in a petrie dish. The size different between the Dapnia and Moina and the unhatched nature of the brine shrimp might mess it up but they may eat the eggs.

Sounds fun.

While working in the lab late one night.....

https://youtu.be/RlaMmkGW2Xo

Dennis

[LizStreithorst]

Who knew that Mr. Spock was a wacko with a sense of humor

[BillT]

Got it set up. Let you know how it works out later.

Meanwhile: