About Phytoplankton

The Missing Ingredient for a Successful Reef Aquarium

Live phytoplankton is an extremely important food for a great many animals that are maintained in reef aquariums. SA’s Live Marine Phytoplankton is concentrated and cleaned to provide nutritious live phytoplankton without the contamination of excessive nutrients or metals from the culture media.

It is very rare for phytoplankton species to survive refrigerated storage. SA’s Plankton Farm only uses species that have been proven to survive refrigerated storage for the entire five month shelf life our “best if used by” date is based on.
Marine reef aquariums can be populated with a variety of phytoplankton feeding animals.

Although some of these animals may feed on preserved phytoplankton, some will reject dead phytoplankton or detritus as food and not consume it. Clams have been shown to reject nonliving partials, passing them instead as pseudo-feces.  Only live phytoplankton will be accepted by all phytoplankton feeding animals.

Phytoplankton is a very important food for marine organisms, because as primary producers of essential nutrients in the oceans, phytoplankton is crucial to the development and survival of most, if not all marine animals at some level.

Phytoplankton are tiny floating organisms (such as unicellular algae, diatoms and dinoflagellates) which serve the same role in the food chains of the oceans as vegetation serves on land; namely small things eat them, which are in turn eaten by bigger things, and so on as the food chain progresses. Many coral reef animals such as clams and other sediment feeding mollusks, soft corals, sponges, feather duster worms, tunicates, copepods and other zooplankton (including invertebrate larvae) feed directly on phytoplankton for all or at least some of their diet. Even those that do not, such as most stony corals, rely ultimately on the nutrition gained from phytoplankton and other marine algae eaten by the zooplankton they prey on. Some essential nutrients gained from phytoplankton cannot be synthesized by animals, and are therefore extremely important components of a healthy diet.

The most important of these nutrients are the class of lipids known as long chain omega-3 fatty acids. One of the major breakthroughs in the aquaculture of marine animals was the discovery that these fatty acids were an essential part of the diet, and without them, nutritional deficiencies or arrested development are common problems.

Many reef-dwelling animals for sale in aquarium stores are sediment feeders which specialize in eating phytoplankton. The poor record of survival in aquaria for many of these animals is most likely a direct consequence of their starvation without phytoplankton being available to feed on. Even if phytoplankton is fed, it will not be of any use if it is not properly stored and in most cases these animals require live phytoplankton. For live phytoplankton to be an effective food, it must either be from actively growing cultures or refrigerated species which become dormant while retaining their nutritional value, which is not common. Most of the species of phytoplankton that are used in commercial aquaculture, such as Isochrysis, Pavlova and Tetraselmis are only effective if fed from actively growing cultures.

Animals which contain symbiotic zooxanthellae, such as corals and giant clams cannot gain all of their nutritional requirements from light alone. The symbiotic algae only provides sugar as a nutrient, and although sugar alone may provide 100 % of the animals energy needs it does not provide the other nutrients, such as complex fats and protein that are needed to grow, reproduce, fight off disease, repair tissue and many other needs. For example, researchers on the Great Barrier Reef in Australia showed that 75% of the phytoplankton passing over the reef was captured and eaten by giant clams (T.gigas); furthermore, juvenile clams were found to obtain 65% of their energy needs from feeding on phytoplankton rather than photosynthesis.