Moina – A Love Hate Relationship

Photo by Dennis Ball

Over the summer, my son’s Red Eared Slider has been helping to generate loads of green water for the fish room.  With this in mind, I though it would be a good time to venture back into culturing some Moina.

If you are not familiar with Moina, they are small freshwater crustaceans, commonly called “water fleas”, belonging the Daphnia family.  I like them because newly hatched Moina average 430 µm and are just slightly larger than the smallest strain of newly hatched brine shrimp.  Also, adult Moina are about half the size of common Daphnia with a higher protein content.  They are simply fantastic live food for small fish.  

In the past I haven’t had the best luck culturing Moina, but this time I’m hoping for better results.  With my supply of green water, and Doug Sweets fantastic paper on culturing Daphnia I ordered some starter cultures on-line.

I placed orders from two different sellers.  My first stop was  They offer a wide selection of cultures to the Aquaculture industry.  I also purchased from Alex at Dallas Discus.  Alex is quick to ship and sends a generous portion to get your culture up and running in short order.

In the past, I have cultured Moina & Daphnia in tanks and plastic tubs, but this time I’m going to try using 1 & 2 liter bottles.  The plan is to start a culture and when the water starts turning clear, meaning that the food supply is about exhausted, harvest the contents and start a new culture in the same bottle.

Sounds like a simple and efficient method, and it will also prevent me from delaying the harvest. My biggest downfall with past attempts at culturing Moina.