Growing Daphnia from a live culture.

Step 1

1 Buy Live Culture from
1 – Buy Live Culture from

Select a clean container of at least 10liters (~2.7gallons) made from food grade plastic, glass, perspex or 316 marine grade stainless steel fish tank.
All of these I recommend.
I personally use 10-55litre plastic tubs or roller boxes.
Cheap, comes with a lid, and is the ideal size.

You may later have success using old 44gallon drums, bath tubs, cattle troughs, even soft drink bottles, ice cream containers and yogurt tubs, but due to the variables in material, chemical, mineral and metal leakage risks, I can not recommend them in this initial delicate establishment stage.

Establish the culture first, keep it happy and healthy for a couple months, then later as numbers build you can split it and do experiments using other containers.
All the while keeping a back-up safe and happy, just in case.

Step 2

2 Hang the bottle inside the container so the water temperature can adjust
2 – Hang the bottle inside the container so the water temperature can adjust

On arrival open the package, and remove the lid.
Replace the lid loosely, and using the high tech flexible wire loop hang the bottle inside the container of rainwater you will be culturing these creatures in.
The temperature of the water in the bottle will be different to the water in your tank and they need to adapt to it slowly.

Step 3

3 Remove the lid and release carefully. Do not pour from a height as it damages and kills them
3 – Remove the lid and release carefully. Do not pour from a height as it damages and kills them

About ~30minutes later carefully add them to the water by submerging and carefully pouring out underwater.

Do NOT just pour them in from a height as this can kill them!
Pouring them in from a height creates air bubbles that can get trapped under the shell of mature adults stopping them from being able to feed and killing them.

It also bashes them around like a car crash, and while it may not kill them, it is just not a nice thing to do..
Slowly and gently folks, remembering the journey via Australia Post has been harsh enough for these poor little guys already.

Step 4

4 Attach the sticker to your container. Wait 1 month. Aeration helps
4 – Attach the sticker to your container. Wait 1 month. Aeration helps

You can apply the easy peel sticker to the culture vessel too, so you don’t loose track of which species you are growing.
Makes it much easier to tell your friends where you got them from too…

Every three days time really stir up the water to break up any algae clumps and allow more food and beneficial bacterial circulate into the water column.
At this early stage you will often see a large amount shells, and the water will look very cloudy and dirty.
This looks bad, may even smell a bit like the sea, but don’t stress, this is 100% normal, and those tiny shells will soon be broken down by the bacteria, used as fuel for algae, all in turn becoming food for the survivors.

As long as you continue to stir the water, roughly scraping the sides every 3 days they will bounce back fine and begin to reproduce again.

If you look closely you may also see tiny grey, brown or black bean pod type of things attached to some of the empty shells.

These are Ephippium, and inside that pod is several eggs which will soon hatch producing even more creatures!

After a couple weeks, when the dead have all disappeared, and the live are looking healthy again, you can begin to feed them a LITTLE extra food if you want.

Do not overfeed!
Cloudy water = too much food = DEATH!!!

Remember that although there may be hundreds or even thousands of creatures visible, they eat algae and bacteria all day long, and this food is already produced naturally in their tank.
It is too small to see, so just trust me on this.

How do I get really high densities?

Aeration WITHOUT air stones in large containers.
Air stones make super small bubbles that get stuck under the shells of mature adults.
This makes them float on the surface where they can not feed and eventually die.
Air stones are also made from rocky sandy minerals that are glued together and shaped around a connection.
This glue and metallic mineral mixture is normally 100% harmless to fish, BUT, it is often very toxic to Cladocera and other mini-critters.
DO NOT use air stones.
If you do, you will nearly always have more “crashes” where they all die unexpectedly, or the reproduction rate will be lower in general.

I use the slightly more expensive 316 marine grade 1/4inch stainless steel Hex nuts.
Do not use normal steel or zinc coated nuts, as that will often kill them via metal leaching.
They fit standard 4mm air hose snuggly, not interfering with the airflow or falling off.
The SAE 316 stainless steel does not rust, corrode or give off nasty chemicals, and it has no effect on growth rates in my trials.
In all honesty, after trialing heaps of different things, these are bloody PERFECT!

Cosy warm temperatures.
If you live in an area with cold night time temperatures then using an aquarium heater set at 15-30celcius(60-85farenheit) will increase your reproduction rates and densities.

~20% water changes using clean aged rainwater every week or so can really help if your plan is continual culture of high densities, or as food for fish.

These guys are crustaceans, meaning they have a chitinous or calcareous exoskeleton. Like a crab, yabby or lobster.
This takes a lot of calcium to produce and if you want lots of healthy critters, then dried shells and sandy grit is a great way to provide it gradually.

I sell small bags of my Shellgrit Substrate Mix here, and although not necessarily, it really does improve general success rates and provide much higher densities, or critters per liter of water.
It also aids the buffering of pH slowing or stopping altogether the swings that algae and bacterial blooms bring.
Even better still, it provides a very porous surface and is the ideal media for beneficial bacteria to grow on, in turn improving water quality and clarity.

Use a food safe container, add rainwater and critters, keep warm and stir every 3days.
= Success!

Use larger container, add more air and calcium

Anything else
= an experiment I have no experience with.
Could be good, could be bad, no idea, so I can’t recommend it.