How to Culture Rotifers to Feed to Your Live Coral or Fish Larvae

Rotifers are tiny invertebrates that often are raised as food for live corals and fish larvae. They are the ideal starter food for species of fish such as neon gobies and certain types of clownfish, which have tiny larvae with very, very tiny mouths. Rotifers can be fed to these fish larvae until the more easily available and more easily cultured baby brine shrimp will fit into their mouths. Rotifers also provide a wonderful source of nutrition for live corals and filter feeders.

However, buying rotifers to feed directly to your tank can be quite expensive. If you need more rotifers than for occasional feedings, I highly recommend raising your own. If you are a reef keeper already you certainly have the skills to do this! Compared to many aspects of saltwater husbandry, it is remarkably easy to culture rotifers.

You will want to buy your starter culture either at your local pet store or from a reputable online dealer. Be absolutely certain the rotifers you are buying are saltwater rotifers.

You will need:

Empty two liter soda bottles

Aquarium tubing

An aquarium gang valve

Small air stones

An air pump

Live, frozen, or powdered phytoplankton

Saltwater mix

Dechlorinated water

A plankton sieve, metal coffee filter, or paper coffee filters

Mix your saltwater according to the instructions on the packaging to a salinity of 1.018 to 1.019 using dechlorinated water and allow it to stand and aerate for 24 hours.

Fill a 2 liter bottle half full with new saltwater. Put in either one very small drop of frozen phytoplankton, enough phytoplankton powder to tinge the water green, or about two ounces of live phytoplankton. Live phyto is best but it is also the most expensive. I have used all three effectively. Live phytoplankton causes the least sediment and pollution.

Shake the solution well and add one ounce of rotifer culture or an amount of encapsulated rotifers per the seller's directions. Wet rotifer cultures take off a lot faster as they do not need to come out of dormancy.

Put the bottle in a warm location and use very gentle aeration such as a low powered air pump with a fine bubble air-stone.