Live food - How to breed phyto- and zooplankton

Barbara asked me to start a thread about the cultivation of plankton.

Now, Barbara, here is the result of what has brought my stupid little brain about cultivating and breeding of zoo- as well as phytoplankton. It was your desire to write about in a separate thread. Actually I wanted to write about it in my seahorses-thread. Not the worst idea to start a new Thread:

So here we go ......

Live food - How to breed phyto- and zooplankton

Most of the common algae in aquaculture belong to green algae or diatoms. Not only therefore it is the diatoms which produce most kinds in the sea and thereby they are also predestined for the use as a feed alga. Green algae take the second place after the diatoms and enrich the palette of the algae kinds. All these algae kinds grow on marine or other saline environments.

As already described most of used algae species are of marine origins. Some of them are from salt lakes. Most “big” algae grow relatively slowly what affects with a raised demand negatively. Hence, as a rule of thumb is valid, the smaller the algae the better and faster it grows, presumed one uses the right nutrient solution.

My primarily used kinds of algae

Algae cultures for amateur breeders


Pisciculture without live food will be mostly an exception, as most fish or cancer larvae are depended on natural, live food. Without a suitable algae culture, it is nearly impossibly to cultivate optimum zoo plankton. Even if most different so-called enrichment feed are offered, there is no substitution for live algae. Algae are, apart from the fact they are a source of nourishment, not to be underestimated as a well-balanced biological environment in the breeding tanks.





Methods of cultivation of phyto-plankton


I am always anxious to use quite special algae fertilizers, as only they offer the algae all nutrients which are required for a ballanced growth. In particular these are vitamins as an addition which lacks the often used flower fertilizers. Many algae will not grow without these vitamins, or only quite meagerly. Also an addition of SiO3 (YES, exactly the SiO3 which we try to avoid in the reef aquarium like the PLAGUE) to the nutrient solution is indispensable for diatoms. During the course of the last few years some excellent additives have been developed as nutrient solutions which can be used either for a certain algae, or for several other uses. One of these "standard nutrient solutions” is F/2 (F/half ones). A significant amount of diatoms can be cultivated with this nutrient solution, yet a corresponding amount of sodium silicate must be added to the standard nutrient solution as these lack silicate. Algae anyway grow best of all with relatively high silicate proportion in the water which many Reefers had to find out quite grievously, after their osmosis filter developed a defect or the membrane filters had become outdated.


The mix of chemicals for nutrient solutions is very costly; nevertheless, one need a perfectly precise chemicals-scales which weigh exactly 1 mg. Moreover, the required chemicals are relatively expensive and are not always available in small amounts. It is an advantage to use already manufactured solutions which must be only measured then and be optimised. Or one uses a ready mixture with all nutrient salt and vitamins. Because vitamins possess a limited life span, it is not advisable to store or to generate larger amounts in a nutrient solution. Vitamins as well as nutrient solutions should be kept in general in the refrigerator and protected from direct light.


Depending on how high the consumption, containers of different size are required. These should be well sealed, so that cultures cannot be contaminated by other organisms. Moreover, sealable containers are substantially better to use than open tanks (However, this concerns only phyto plankton, not zoo plankton.). Various so-called plankton reactors which have all their advantages and disadvantages are available in retail. Rather easy and inexpensive possibilities are PET plastic bottles. I’m using 5 litre PET plastic bottles with great success for some years now. In bottle cap of every bottle I have drilled a hole in which an air-hose can be inserted. The air hose constantly whirls up the solution and provides at the same time for an optimum level of oxygen and CO2. Thus it is prevented that the algae retreat or that they grow on the bottle walls. Some algae such as Tetraselmis, grow fast on the walls of containers and thus prevents that light enters the container or bottle. All algae commonly have an inclination to settling on a surface - some more, some less.


In previously mentioned reactors one prevents this by the use of a magnetic stirring mechanism. This stirrer is very suitable with small amounts of algae. However, with increasing quantities of water they become more sluggish and the algae will quickly grow on the walls of reactosr. Additional manual shaking of the reactor will not improve the algae growth performance. Yet the shake of the bottles leads to a substantially higher yield in algae mass.

Breeding Zoo- and Phytoplankton - Phytoplankton in PET-bottles - Zooplankton in 25 liter tanks

That all bottles, as well as any other containers that are needed for cultivation has to be germ free is logical. Sterilisation of the nutrient solution can happen on the most different ways. Heat sterilisation is out of question because of destruction of vitamins. There remain different possibilities to make the solution with the help of filters aseptic. Steril filters are to be used only once and therefore not quite reasonably. However, they offer an absolute sterility of the solution. More reasonably, but not 100% in the application are UV filters. But also UV light destroys vitamins in solutions. You can sterilise alternative salted water with UV-C and adds the nutrients by means of sputter filter afterwards. This solution comes closest to a proper sterilization and shows likewise good growth results. The bottles themselves become after thorough cleaning and rinse with clear water, sterilised best of all with pure alcohol. Denatured 75%Th alcohol is the best for it suitably there this over and over again can be used. Rests of the alcohol in the bottles are rinsed with a little bit sterile water. By no means these rests should remain in the bottle, because they would be a good fertile soil for bacteria and allow tilting thereby the whole culture. The bottles are “inoculated” immediately after addition of the nutrient solution. For a good growth it is necessarily an adequate amount from “vaccination material” is added. In practice a relation from 1:5 -1:10 has turned out best. In to the 5 litre bottles at least 1 litre inoculum should be added. Is added not enough, a very delayed or generally no growth mostly takes place.


The algae are “harvested“ as soon as the respective algae-bottle has a full dark-green colouring. According to algae species and growth terms this can be after 1-2 weeks. If the culture is clean and without signs of zoo plankton for example, it can be used immediately to inoculate new cultures.




Cultivation of zoo-plankton


As previously described, it is essentially to draw up living feed in the right size independently for the breeding of marine fishes. In my opinion, Copepods or even zoo plankton cultivation may make an important contribution in home aquaculture, when fish fry are too diminutive to eat rotifers as a first food. Brachionus plicatilis are best suited. On the one hand, they are very fond of increase after my experience and secondly are still very nutritious with the right breeding feed. Mostly the breeding stocks are not pure so that still other plankton is bred. This is to be valued in no case as a disadvantage. It depends of course on the amount which one needs to be able to supply our fry’s.


I began first zoo plankton breeding with 5 tanks (25 cm x 35 cm x 40 cm (45 litre), as to see in picture above (left picture side), this is perfect enough for a "hobby zoo plankton breeding". For a sufficient care with oxygen I used so-called "Airlift pumps" (as to see in the picture below) in each of the aquariums. 3 Air bubbles per second provide for adequate movement.

These also provide a sufficient surface movement of the solution. Tanks are illuminated with T8 10,000k; however, energy saving lights (6.500k) are suitable as well. In this order appears, unheated, a temperature of approx. 22-25°C. In this temperature-area the increase rate is quite optimum. Brachionus plicatilis and other Copepod populations are located in habitats where salinity ranges from almost fresh water to >35ppt. They can withstand temperature ranges from 10 - 28°C and water quality that is quite suspect. By the way …. Salinity! It is best to match the culture tank to the tank to be fed. This helps eliminate the possibility of salinity shock for the Copepods or Brachionus when they are finally fed.

Brachionos plicatilis eating algae

Zoo plankton culture

Example for a Schedule of a slowly growing zoo plankton culture

After 14 days plankton density should be high enough to be able to infer daily enough Brachionus or Copepods. According to the number of fish, seahorses or shrimps in breeding-tank the amount is enough for 100 - 120 freshly slipped fry’s!


Attention: If the water does not clear up after one day, the feed amount must be reduced! Here everybody have to find out the ideal feed amount. The above table should show merely a help to the very first beginning.


The water in which the Brachionus or Copepods live is loaded very strongly by Culture Selco 3000 and algae with nutrients! Hence, it is not advisable to give Brachionus or Copepods with the water in breeding tank or tank (DT).


To move the Brachionus or Copepods I use a plankton-filter (11 μm - 200 μm). I pull this several times by the water, let it drain and rinse the filter directly in the breeding tank.




So Geek's, that's it .... hope it is helpful.

Heinz , great post !

Great post Heinz. We have never tried to grow phytoplankton but we might give this a shot this summer and see how hard it is.

THANK YOU Heinz!!!! this is a fabulous reference for anyone wanting to culture phytoplankton (like me ) ... and it's in it's own thread too! Easy to find for future reference ... though when we do get started I'll have a few questions that I hope I can call on you to help us with??

Wow great post


Now I need to sit down and really read it and try it myself

very informative post.

yeah heinz thanks for the info very informative in did

Heinz so in total , how many tanks do you have ?

Originally Posted by Thinkin Reef

Heinz so in total , how many tanks do you have ?

How many tanks in my breedingstation Andrew or in total including my fish and coral tanks?

Including your fish and coral tanks as well Heinz

Originally Posted by Thinkin Reef

Including your fish and coral tanks as well Heinz

OK Andrew... I have 16 PET-Bottles for Phytobreeding, 16 Tanks for Zooplankron breeding, 4 breedings tanks (seahorses, gobies etc.) 1 Mediterranean tank, 1 coral tank and 1 fish only tank .... ll together there are 23 tanks

Wow !!

Just out of interest ,Heinz how many hours a week do you spend on your tanks?

Originally Posted by Thinkin Reef

Wow !!

Just out of interest ,Heinz how many hours a week do you spend on your tanks?

When I'm at home, every day approximately 30 minutes and at the weekend about 3 hours for ALL tanks.

What ? holy crap Heinz
"they must run themselves by the sounds of it !"

Great thread Heinz, I will have to give this a go soon.

Originally Posted by skinz78

Great thread Heinz, I will have to give this a go soon.

I'm glad. You'll see, it is quite simple, you need only follow the rules and fill the tank steriel. There will also be the one or the other failure but that we are all fighting for.

Good luck

Ok I'm following all these instructions and can not keep my phyto alive for some reason, thus I can't keep my rotifers alive.

I have a rumble for the air flow and I add one to two drops of macro algae grow in the bottles each day. I can't get it to darken so I can split it. The water I'm using is around 1.019. Any thoughts?

a question on the F2. How much do you add to each 2L bottle per day?

Do you keep it the same no matter what density it is or adjust it for the darkness?