Looks like a scene from "Jar Wars",
but it's really a drawing of daphnia
many times larger than life.
What are Daphnia:Daphnia are a very small freshwater shrimp like creatures. They are found in small pools, ditches and ponds all over the world. They thrive best where there is an abundance of food for them. They are filter feeders, that is they swim around and filter the water for smaller organisms. They eat rotifers, algae and infusoria. Serious oldtimer Aquarist used to go on collecting trips for daphnia every weekend and they considered daphnia the best fish food available. I don't advise collecting wild daphnia because of the potential of possibly bringing home diseases, parasites or other undesirables along with the daphnia.
Getting Some DaphniaDaphnia are hardly ever avaliable in petshops, I have no idea why. But if you want to try them your best bet is to start a culture of your own. You can buy a starter culture from fellow aquarists or try a place like Aquabid.com which usually has some listed and I am currently offering starter cultures on the Stock Shop.
What you need:
- 2 one gallon jars or something similar
- siphon hose (ie airline tubing)
- brineshrimp net or the toe part of a ladies pantyhose
- A source for algae or some bakers yeast
- a bubbling air line
- a brightly lit place to keep the culture jars
One trick that I find especially pleasing is to put 10 to 20 or so adult daphnia in a fry tank. Though the daphnia are too big for the fry to eat, any baby daphnia they have will make good food, (they are smaller than baby brine shrimp) and the daphnia help keep the water clean. Of course you don't add any daphnia food to the fry tank.
There are several types of Daphnia commonly available. Daphnia Magna is about the biggest (about Brineshrimp size), followed by Daphnia Pulex a little smaller, and then Daphnia Moina, the smallest. I prefer the Moina because they are happy in water that is around room temperature, 70 to 85 F, (it's HOT in Alabama) while the other species require lower temperature, around 55 to 68F.
All species will do great outdoors in the warmer months. I use a kids swimming pool. Just throw in a handful of plant food fertilizer to get the pool green with algae first and then add the daphnia a few days later.
One of my Daphnia Moina culture jars, right after feeding yeastwater.
Note that you just want a slight haziness.
Notice the airline tubing, and yes that is a snail, doesn't hurt a thing.
Also adding a little marine type aquarium gravel or oyster shell will give
the daphnia a buffer from a low pH and supply them with needed calcium.
I have read that it's not good to keep the lights on a daphnia culture all the time, but as a constant experimenter, I tried it anyway. The results were outstanding, the daphnia have doubled to tripled their production. I've been doing this for 2 months now, so there has to have been several generations raised in constant light. So far there are no bad side effects, other than having to feed the daphnia everyday as opposed to once every 3 days before. I am currently using a 10 gallon tank with an old incadescant aquarium light fixture. I feed the daphnia about an 1/8 teaspoon of bakers yeast a day, and harvest about a 1/4 to 1/2 teaspoon of daphnia a day, everyday! Also in the tank are 100's of snails and I throw them a small leaf of lettuce every few days. An added benefit to the constant light is that the fish now have a night light, and I put microworm cultures on top of the light, the heat makes the microworms multiply and grow much faster.
This entry was posted on Friday, September 04, 2009 and is filed under Koi feed .