Raising Daphnia

Daphnia, or also known as water bugs, or water fleas, are freshwater bugs that are extremely easy to cultivate and are a good source of food to induce breeding, get fry the necessary protein they need, and make other fish chase around their prey more. Something that is extremely unique about daphnia when compared to other live foods that you can feed your inhabitants, is that they will stay alive and swim around until something eats them.

Starting Requirements

In order to start growing daphnia in your own setup you may need to have a clean, unused container, airline tubing, an air stone or bubble wand, an air pump, a light source, a thermometer, a package of dry yeast, a package of soy flour, and a starter culture of daphnia.

  1. Find a starter culture that contains the eggs in a powder or crystal form. Many aquarium stores or aquarium groups should be a good place to get the culture from, otherwise you can try buying online.
  2. Use a container that you plan to use as a permeant home for the daphnia to thrive in, however make sure that the container can fit somewhere that gets indirect light throughout the day (using a lamp will work as well if you plan to grow them in a dark spot, or do not have access to sunlight as frequently as others do).
  3. Add a water source that has no chlorine in it (make sure to use a water conditioner if so, or use bottled water) and pour it into the container.
  4. Connect the air pump to the airline tubing, making sure to have one end connected to an air stone or bubble wand. Place this inside of the container, making sure that the air pump is turned on an extremely low setting (we only want water movement so that the water does not get stagnant and also so that the oxygen does not get depleted).
  5. Place the thermometer inside of the water container in a good spot, as we need to make sure that the water stays around 72-75 degrees Fahrenheit (22.22-23.89 degrees Celsius) at all times.
  6. Mix one package of dry yeast with one cup of soy flour. This will provide the daphnia with their food source, make sure to stir roughly 1/8-1/4 of a teaspoon of this mixture into a cup full of warm water before pouring it into your container.
  7. Wait until the water is crystal clear (or clear enough) before adding any more of their food source, otherwise overfeeding will result in their death due to the water getting foul.

Feeding and Care

We highly recommend that you avoid using any type of filter, as it will catch the tiny lifeforms that the daphnia feed off of and may even catch the daphnia when they are small enough.

  1. Make sure to do regular water changes to keep the water quality at its highest, along with harvesting them on a regular basis (if you don't want to lose any daphnia, then use a shrimp net when removing water to catch any).
  2. You might notice the food mixture to leave a big residue at the bottom of the container (this is called a mulm). We recommend that you remove this on a weekly basis in order to avoid the water fouling or for there to be a lack of oxygen.

Whenever you are getting ready to feed them to your inhabitants, you can always make sure that you siphon out the smaller ones for any fry that you have, leave the medium sized ones for your normal inhabitants, and the large ones for the bigger inhabitants you might have.