Page Updated 4/09/24

Live Foods

8/8/22 Chlorella vulgaris starter kits in stock and shipping.


Culturing Chlorella vulgaris Chlorella vulgaris Starter Kit

Live foods are vital to the good health and nutrition of aquarium fish. They are what fish eat in nature, and a necessity for successful breeding and raising the fry. Here below are the live food cultures I currently offer for sale, and instructions for culturing and using these and other live foods.

The Four Nematodes: Micro Worm (MW) - Banana Worm (BW) - Walter Worm (WW) - Vinegar Eels (VE)

These four nematode worms are indispensable as first or second foods for the fry of almost all freshwater aquarium fish. They are simple to culture and maintain and all but the vinegar eels get started very quickly. The MW, BW and WW are all cultured on solid medium like oatmeal, and the VE are cultured in a jug of cider vinegar and water.

Micro worms climbing sidewalls

They differ mainly in terms of size, reproductive rate, and how long they stay alive in water. The differences are not visually apparent at the level of individual worms. They become apparent at the level of a whole culture.

You should always plan ahead and have cultures going before fry arrive, especially with vinegar eels that usually take four to six weeks to get going. Once a VE culture does start producing though, it can last up to a year! With little to no maintenance required, it is a good idea to just start and keep a jug or two of vinegar eels running just in case.

Vinegar eels

All four have about the same high nutritional value, a close second in many respects to newly hatched baby brine shrimp (BBS). The comparison table here below summarizes the important differences. If you are hatching really tiny fry like bettas, you want walter worms and vinegar eels. You can start larger fry that are still too small for BBS right away on banana worms or micro worms. Micro worms are also good for fry growing out and even smaller fish like neons, juvenile guppies, or badis.

Nematode Comparison Chart
Species Relative Size Doubling Time
Micro Worm Large Longest
Banana Worm Medium Fast
Walter Worm Small Fastest
Vinegar Eel Small Very Slow
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Micro Worm - Banana Worm - Walter Worm - Vinegar Eel Cultures For Sale. Two, Six and Ten Ounce Cultures Available.

Two Ounce Starter Pic

Two Ounce Starters

These low cost starters are available for all four nematodes: micro worms, banana worms, walter worms and vinegar eels. The vinegar eels take four to six weeks to get going well, and the micro, banana and walter worms at least one week in a sandwich-size container.

All cultures come with a packet of yeast to help start up, and pipettes that can be used to feed the worms to your fry. Culture instructions with pictures are available on this page for easy reference. Two ounce starter pricing is here below:

Two Ounce Starter Culture Pricing - Shipping Cost Combined On Multiple Purchase
Pips = Pipettes
BW = Banana Worms
MW = Micro Worms
WW = Walter Worms
VE = Vinegar Eels
Species Pips Price Ship Item Code
Choose 1 of BW - MW - WW - VE 3 $4.30 $3.85 1C
Choose 2 of BW - MW - WW - VE 3 $6.30 $3.85 2C
Choose 3 of BW - MW - WW - VE 4 $8.30 $4.10 3C
Choose 4 of BW - MW - WW - VE 6 $10.30 $4.35 4C
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Six Ounce Quick Start Culture

Six Ounce Culture Pic

This is a larger culture used to start multiple mother cultures OR as shown below, be used out of the bag as a medium Ready To Feed (RTF) culture so you will not have to wait a week to feed those hungry fry.

The image to the right was taken 30 minutes after a quick start culture was placed in the container. The worms are already climbing the sides and ready to feed with the swipe of a finger. While you are feeding from these mature cultures, you can take a couple spoon-fulls and start a new mother culture going per the very complete instructions you get when you purchase your culture. This culture has simply been poured into an empty container. For even more versatility you can pour it over a quarter to half inch of cooked oatmeal and start a culture while feeding from it!

Six Ounce Quick Start Culture Pricing - Shipping Cost Combined On Multiple Purchase
Pips = Pipettes
Species Pips Price Ship Item Code
Micro Worms 6 $10.50 0.00 QM
Banana Worms 6 $10.50 0.00 QB
Walter Worms 6 $10.50 0.00 QW
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Extra Large Ten Ounce Ready-To-Feed

Ten Ounce Culture Pic

This culture is over a half pound of mature mother culture ready to feed as many fry as you have. You can feed from these very shortly after set-up, and there is plenty to start a backup or two as well. The culture comes in two, 5 ounce bags that are the working upper portion of one of my shoe-box mothers transported to your fish room.

Extra Large Ten Ounce RTF Culture Pricing - Shipping Cost Combined On Multiple Purchase
Pips = Pipettes
Species Pips Price Ship Item Code
Micro Worms 6 $14.85 Free XM
Banana Worms 6 $14.85 Free XB
Walter Worms 6 $14.85 Free XW
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How To Culture Micro Worms - Banana Worms - Walter Worms

Begin by preparing a container for your culture. Here I use a sandwich size plastic container and cut a rectangular vent in the lid, covering it with thin muslin cloth to keep pests out. The cloth square is taped in place along its edges.

Culture container

Once the container is ready, put about 1/2" to 3/4" of cooked, COOLED, oats in it. They should be shiny-wet but not soupy. Oats that are too dry will mold. I prefer the Old Fashioned oats that cook for five minutes because they hold up longer than the instant. Some use mashed potatoes or even a slice of bread. Many sources of carbohydrate will work.

NOTE: These instructions are based on using a two ounce starter. If you have a larger amount of starter or a Ready To Feed (RTF) culture, then use a larger container. Size it so a 1/2" of oats topped with your starter brings you to less than an inch total depth. You always want more surface area and not too much depth.

Culture container with oats

If you got your starter from me it will be sealed into a plastic bag. This happens to be micro worms. The easiest way to get the starter into your container is to snip off one corner and then pipe it out like cake frosting.

Culture container

Starter placed on medium. I always ship a little extra so no worries about the small amount left in the bag, just toss it.

Culture container with oats

Your culture is ready to close up and put on a shelf somewhere out of direct sunlight. A cool place in the room temperature range works well. They will be fine in any temperature you are comfortable in. They toleratecold better than heat, and a culture will cycle faster in higher temps, shortening it's useful life.

Culture container

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How To Culture And Harvest Vinegar Eels

Vinegar eels are by far the easiest live food to culture. I've got jugs that have been working for more than a year. To start a culture, rinse out a gallon jug and fill it to where it begins to narrow with a 50/50 mix of cider vinegar and dechlor water.

04/09/24 I have found that using pure cider vinegar, without the water cut, makes my large, one gallon cultures last longer and does not in any way injure the worms or cut production.

Then add four or five slices of peeled apple. The skin can contain pesticides. Finish by adding the starter and plugging the jug with fliter floss or rubber-banding a thin cloth in place to keep out flies and allow air in.

Vinegar eel culture materials

Date the jug and put it in a cool dark place at room temp and that's it. Agitate it once a week or so with a $store baster and you'll be ready to feed from it in 4-6 weeks. I advise starting a second jug about three weeks in using a few ounces from your first jug as a starter.

A month or so later.........To see if your culture is ready to use, pull some up in a baster and check with a magnifier or just viewing with a light source behind the baster. When you see lots of vineger eels it is ready. I harvest with a coffee filter put in a funnel made from the cut off top of a two liter soda bottle. You can also get a funnel at the $store. Put a few ounces of your culture into the filter and let it drain completely. The funnel sits in a clean catch jar.

Vinegar eel culture materials

Here the vinegar has drained into the catch-jar and the vinegar eels are in the filter paper.

Vinegar eel culture materials

Return the filtered vinegar to the culture jar. If the culture is older and is starting to lose its sharp vinegar smell, then just discard this filtered vinegar and add fresh vinegar water mix to the culture.

Vinegar eel culture materials

Use fresh water to rinse the vinegar off of the vinegar eels in the filter paper. Toss the rinse water afterwards.

Vinegar eel culture materials

Collect the vinegar eels by turning the filter paper inside out and swishing it thoroughly in a container of fresh dechlor or tank water.

Vinegar eel culture materials

Vinegar eels harvested and ready to feed to fry.

Vinegar eel culture materials

Feed the fry! A very small live food that swims and triggers the strike response of very tiny fry, and stays alive and doesn't foul the tank.

Vinegar eel culture materials

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Micro Worm - Banana Worm - Walter Worm Culture FAQ

Abbreviations: MW = Micro Worm, BW = Banana Worm, WW = Walter Worm

They are nematode worms, also known as roundworms. There are about 25,000 species identified so far out of a total of perhaps 1,000,000.

Nematodes are difficult to identify even for experts. The differences between these three are best seen at the level of whole cultures and with experience. MW are the largest, reproduce slowest and don't stay alive quite as long as the others in water. BW and WW are smaller, reproduce faster, and last a bit longer in water. Some say the WW stays up in the water column longer, but I have not verified that. For smallest fry I use WW. For larger fry and small fish I use MW. The worm 'in the middle' in most respects is the BW.

They reproduce sexually and drop living young. Using the microworm as an example, they release 10 to 40 young every 1 to 1.5 days for a 20 to 25 day life span. Therefore, each female produces approximately 300 young. The young reach sexual maturity in approximately three days. Their size increases by three times during the first day and five to six times during the next three days. The live nematodes are 76% water and 24% dry matter; 40% of the dry matter is protein and 20% is fat.

They do not eat the medium! Free living nematodes like these are bacterivores, meaning that they eat very small organisms like bacteria and yeast cells. So why the oatmeal? The oatmeal, or any other carbohydrate that you use, is broken down by living yeast cells and bacteria that in turn are eaten by the worms. It is a miniature ecosystem wherein yeast 'eats' the carbs in the oats, then the worms eat the yeast.

oats > are digested by > yeast/bacteria > that are eaten by > worms
A heathy culture doesn't need to be fed after it is started. As per my instructions above, you can add a pinch of yeast to help seed your culture when you set it up. After that, the yeast lives and multiplies in the culture and no more needs to be added. It is the action of the yeast that breaks down the medium, oats in this case. Adding a lot of yeast may 'put the pedal down' on a culture and accelerate its growth, but that also shortens its useful life. A pinch at startup works fine, and perhaps another if it is not growing, but always take it easy with yeast.
At startup it should be shiny-wet, but not soupy and runny. Cultures that are too dry to start with will end up molding, but you'll never see mold in healthy culture because the worms can easily get to it and consume it before it grows out. If you see mold, skim it off and stir in some water. As a culture ages it will naturally get wetter and runnier because enzymes from the yeast are breaking down (fermenting) the carbs in the medium.
Any temperature you are comfortable in works for these cultures. They are more tolerant of cold than heat, and are good down to just before freezing solid. When cold, they just slow down and will go dormant til warmed back up. Temps above 90 (F) are dangerous for them. As temps go up, cultures reproduce faster and age quicker. Cooler, and they take longer to mature and therefore last longer. Heat=Faster / Cold=Slower.
I advise always having a backup culture going in case your older culture crashes suddenly. It is a good idea to start your backup as soon as your mother culture gets going strong. Just setup a second container and use a few spoonfuls of live culture as a starter.
That depends on several factors, but at least a few weeks and with care longer. A healthy culture smells somewhat 'yeasty' but not foul like something rotting. As cultures age, waste and dead worms build up and the odor starts to get a little worse. Color changes with the medium darkening also signify that the culture is preparing to 'turn.'
Once a culture is going well, stir it up thoroughly at least every other day. This aerates and prevents anaerobic bacteria of decay from building up in the lower reaches. When it looks like it is starting a downturn, you can further extend it by removing a half to a third of the medium and stirring in fresh, slightly drier oats. With care a culture can conceivably go for a couple months.
You can use all sorts of containers. The worms mainly live on and near the surface of the medium, so the best containers are relatively shallow, with a lot more surface area than depth. I find plastic tupperware style containers from the $store work very well. They must have a cover that can be sealed and that you can cut an air vent into. In the tutorial above I use a sandwich size container, but in practice I keep 12 to 16 plastic shoe box cultures going.
Once your culture develops a large enough population the worms begin crawling up the sides of the culture container. The less squeamish simply swipe a finger along the container wall and swish it in the fry tank being fed. Equally easy is keeping an old teaspoon next to the culture and swiping it along the wall to gather worms and transfer to the tank. I supply plastic pipettes with all my culture purchases, and you can collect worms as above, transfer them to a small container of water, and then use a pipette to feed fry from that container.
Happily, nematodes are one of the easiest and least problematic live foods to culture. In warm weather, fruit flies seem to be able to get under most lids and lay eggs in the cultures. You can deal with the immediate problem in a given culture by first getting the winged flies out of the container (outside). When the maggots in the culture are ready to pupate, they will climb up on the sides and lid and turn into little, brown cocoons that are easily popped or removed. To avoid this altogether, either get containers with fly-proof lids, or simply keep your culture containers in pillowcases that are twisted and rubber-banded shut. Sometimes a culture develops a very thin, cloudy, white film on its surface. This is actually more serious than flies since it cuts off oxygen to the culture below and can smother it. I think it is an aerobic bacteria or form of yeast, since it appears to be alive and reproduces. It seems to happen less in mature cultures with very heavy worm populations, which may help keep it down. The only remedy starts with not spreading it to other cultures with hands or spoon, etc. Then, using a large spoon skim it off the affected culture, and very thoroughly stir it up to submerge the small bits you've missed. Sometimes this works, sometimes not, but I know of no other way to fight the scum!

Container Prep For Grindal Worms
As of April 2024 we are not stocking grindal or white worms. 

Here I am using a 12" x 8" size shallow, plastic, food storage container. These are readily available at most $stores. Surface area is more important than depth, and 1" is a good depth for these worms.

Cut a vent into the lid and cover it with a piece of thin muslin cloth taped in place around the edges. Air passes through this and pests are blocked. A yard of this is just a few bucks at Walmart or a fabric store and lasts forever.

You can use any size container you wish. Some use a smaller container at first then expand to larger containers as the culture grows. Use the same construction for any size container.

Culture container

Next add the medium. Here I am using a mixture of coconut fiber called coir and vermiculite. The coir is inexpensive and readily available on Amazon in compressed bricks. I hydrate mine in a 5 gallon bucket per directions on the brick, then cover it and store in the same bucket. Using boiling water to hydrate also sterilizes it.

The vermiculite buffers moisture and moderates the compacting of the medium as the culture ages. Proportions aren't critical, but 60/40 coir/vermiculite is a good mix. Mix the medium thoroughly with a clean spoon.

Culture container with medium

You can also use potting soil that does not have any fertilizer or other additives. CAUTION if using potting soil you must sterilize it thoroughly to avoid introducing mites. Dampen it, then sterilize by either microwaving for several minutes until it is quite steaming hot, or by baking it in a conventional oven at about 300F for a half hour, again until it is steaming hot. Mix it intermittently during this process to make sure it is cooked through to kill any mites or eggs. You can also boil it then cool and dry it.

Culture container with medium

A cover plate is needed for the medium. Any lightweight, preferably transparent plastic will do. In the past I've used clear mylar sheeting from the craft store, but recently I've come across these translucent plastic mats that are two for $1.00, at the $store of course!

Trace the outline of the bottom of your container, then cut it out

Cutting the culture cover plate

Ideally it will just about fully cover the medium in your culture container. Verify that it fits well, then set it aside while you finish preparing the medium for the introduction of worms.

Cover plate on medium

Judging the proper moisture level is a learned skill. Moisture builds up as a culture ages, so it needs to be moist but not too wet to begin with. A spray bottle of water ($store again) is a good tool for adding water. Give it a few spritzes, then using the spoon work the water in evenly, breaking up clumps.

Spraying water on culture medium to wet it

When the medium just holds together when squeezed, and no water comes out you are at a good point. Remember it is much easier to add moisture than it is to remove it, so take your time.

Squeezing medium to check moisture level

Container and medium are now ready! Time to add grindal worms and start your culture.

Container and medium ready for worms

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How To Culture Infusoria / Paramecium

Infusoria refers to the many microscopic and near microscopic life forms found in fresh water habitats. When the smallest fry hatch in nature, infusoria is their first food. It is small enough for them to swallow, and it moves, triggering their strike reflex. Raising very small fry in the artificial environment of the fish room is challenging. Your chances of success increase dramatically if you provide the live micro foods needed to get the fry through those critical first days.

paramecium photo

Paramecium are the primary organism in the infusoria cultures used in the hobby. They are single celled, slipper shaped, and move effortlessly using a fringe of tiny hairs called cilia as synchronized oars. The cilia also direct food into their oral groove which functions as a mouth. They are bacterivores eating bacteria, yeasts, and single celled algae. They are just visible to the unaided eye as white specks, and at an average 225 microns the species I work with are about half the length of a newly hatched brine shrimp nauplii. Their diameter though is just a fraction of that of the brine shimp nauplii. Reproduction is primarily by fission (dividing in two) and occurs two to three times a day depending on temperature, with warmer temps speeding up division. Life span is measured in divisions, and is usually between 200 and 300 divisions.

paramecium diagram

The first step in culturing paramecium is selecting a container, and getting a bacterial bloom going to feed the paramecium. They are bacterivores, consuming bacteria, yeast, and some species of cyanobacteria. I am using a cut-off, clear, two-liter Pepsi bottle for this tutorial. It is well rinsed out and filled with dechlorinated tap water at room temperature. If you are comfortable, the temperature is fine for paramecium. Several pieces of lettuce are added, and I put in four or five drops of milk to kickstart bacterial growth.

The paramecium do not eat the lettuce. It is broken down by bacteria of decay, and it is these bacteria that the paramecium feed on. You could use some rice or wheat grains, or another leafy vegetable. I like lettuce because I can dehydrate a whole head of it and store it in a baggie for use as needed. Once the culture is set up I label it with the start date and put it on a shelf in the fish room.

culture container

In 24 to 48 hours you should see the culture starting to cloud up. That is the bacteria breaking down the lettuce, and means it is ready for paramecium to be added.

paramecium culture container

If you are using one of my four ounce paramecium starters you should order it when you start the culture container, so it arrives just about when the container is ready for seeding. This starter contains paramecium from my long running mother cultures. There are enough to get your culture going in four or five days.

Paramecium and other infusoria are usually present in our tanks. If you want to try culturing without a starter, you can hunt wild protists in the bottom mulm and among javamoss and other plants, in filter sponges and filter floss, and in your substrate. Collecting samples from all of these places and using them to seed the culture will sometimes produce a good mixed infusoria culture. If you go this route, just be sure to avoid introducing planaria and other unwanted guests.

starter culture

While they are large enough to be seen with the unaided eye if your vision is good, I suggest getting a magnifying glass for a clearer look. A good magnifier is a very useful tool in the fish room, and a worthwhile investment. I also include pipettes to help with harvesting and and transferring paramecium.

starter closeup

Here at four days since seeding, the culture is doing well and populated enough to harvest from. These cultures have a cycle that starts with a big bacterial bloom, followed by a surge in the paramecium population, and a corresponding decrease in bacteria. I harvest with a pipette or baster, and pull from where the paramecium are thickest, usually around the dacaying lettuce. When the paramecium population goes down, adding more lettuce or whatever you are using to promote bacterial growth bumps up the paramecium population.

mature paramecium culture

If I'm feeding a small container like a petri dish, then drops are in order. Larger fry containers or small tanks can take more. Unless you are raising fry by the natural method, it is good practice to start them in smaller water volumes. Fry should literally swim in their food.

The culture water has an ammonia level, so don't overdo it. There should be a lot more fry container water than added culture. A little goes a long way too, since this is a food that stays alive until eaten! If filtration is used in the fry container, turn it off or down for awhile when feeding this, since it can be taken up in the filter. Using paramecium the first few days with really small fry significantly improves survival.

different culture containers

These cultures do produce an odor as the bacteria count peaks. I always put a loose cover on the cultures to help contain it and keep pests out. A round plastic cover like the one that comes on oatmeal boxes works well. Culturing in unmodified two liter bottles, as shown above, is another way to minimize odor. Some have a filter floss plug, while others just have the cap sitting loosely in place, allowing the culture to breathe. To feed from the narrow neck bottles just pour a bit of culture out into a small, open top container.

To keep a culture producing, when the medium clears simply add a bit more lettuce or whatever you are using instead. This should generate a fresh bacterial burst, and a corresponding increase in paramecium. After two or three weeks, you can start a second bottle to have one going when the first gives out. Using smaller amounts of lettuce in backup cultures creates smaller paramecium populations that are more sustainable for a longer time. When needed to feed fry, you can add more and start fresh cultures.

Feel free to experiment with different 'foods' for these cultures. I am currently working with yeast as a possible alternative to bacteria of decay. There are also a number of alternative techniques to explore on YouTube. As with most aspects of the hobby, there are many ways to achieve a good outcome! I usually have these starters in stock and they can be ordered by email or contact form from this website, or from the live foods section on AquaBid, where I sell as fishguy_1955. Pricing is here below.

Paramecium Starter Culture Pricing - Shipping Cost Combined On Multiple Purchase
Pips = Pipettes
Size Pips Price Ship Item Code
Four oz. 6 $6.30 $3.85 P4
Six oz. 6 $8.30 $4.10 P6

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Culturing Vinegar Eels Like Microworms
The Hyperdense Vinegar Eel Culture

04/09/24 New media prep method presented

Harvesting the vinegar eels from this liquid culture requires several steps to separate them from the vinegar before you can feed them to your fry. Wouldn’t it be great if they remained simple to culture, and were as easy to harvest and use as micro worms?

traditional vinegar eel culture photo

It turns out there is an easy way to culture vinegar eels (VE) just like micro worms, on semi solid medium like oatmeal or mashed potatoes, and harvest them with a simple finger swipe or a Q-tip! About two weeks into the first experiment with this technique, I thought it wasn’t going to work, then in weeks three to four the first cultures took off. Knowing that it could be done, the next step was to find a way to do it simply, and a lot faster than three to four weeks. Those first solid media cultures were the key. I can now use a six ounce hyperdense starter to start a vinegar eel culture that is ready to feed from in a day or less after setup. These cultures last longer than micro worm cultures, up to a couple of months or longer, and are very simple to keep going.

I want to thank my friend Mark Plessner for his help in running multiple trials to arrive at the optimal media. His assist cut a lot of time out of the process!

hyperdense vinegar eel culture photo

The key to this technique is starting out with, and maintaining a very large number of vinegar eels in a small space. High population density is what makes it happen. My six ounce, solid media starter contains many times more VE than a much larger liquid vinegar culture, where they are spread very thin.

culture container highlighting top layer

What about the vinegar? Do these cultures do away with the vinegar? No. Vinegar is still used and the worms help out by leaving it for harvesting. The vinegar preserves the media, extending the culture’s life. It also promotes the growth of the specialized bacteria, Acetobacter aceti, that is the vinegar eel’s primary food.

The culture is a miniature ecosystem with a carbohydrate, oats or potatoes, at the bottom and the vinegar eels at the top. Yeast breaks down the carbs in the media, converting it to alcohol. Immediately, the Acetobacter convert that alcohol to vinegar. All the while, spoilage bacteria are trying to work on the oats, but the acidity of the vinegar keeps them in check. The vinegar eels swim in this sea of food, eating the yeast, Acetobacter, and spoilage bacteria. They do not consume the media.

culture food chain diagram

Within hours to a day, cultures started per instructions, using the six ounce starter in a sandwich size container will usually have worms crawling the container walls. Harvesting them is as simple as swiping the edge of a finger along the inside wall of the culture container, and swishing the worms thus collected into the fry tank or container. Some may choose to use the edge of a spoon or a Q-tip. Vinegar eels can be harvested and fed to fry in about a minute. As one who has used the traditional, liquid method for decades, I am still amazed by the speed and simplicity of this technique. Some may want a standard, liquid, vinegar eel culture as a backup.

vinegar eels on spoon

six ounce starter culture

Hyperdense Vinegar Eel Starter Pricing
Size Pips Price Ship Item Code
6 oz. 6 $12.00 $0.00 HDV6

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Hyperdense Vinegar Eel Culture Instructions
Using a Six Ounce Hyperdense Starter

Begin by preparing a container for your culture. To ensure the culture gets going in a day or two, you need to use a sandwich size container. Larger containers will take longer to get started. Vent the lid so the culture can breathe. Screen the vent to keep flies out. I tape a square of thin cloth over the vent, you could use paper towel if you keep it dry.

vinegar eels container

As of April, 2024 I'm updating instructions for media prep with what I've learned doing this over the last several years. Whichever medium you use, oats or instant mashed potatoes, you prepare it by simply soaking it in pure cider vinegar for a few days. I start by filling a quart size yogurt or deli container about 2/3 full with old fashioned or quick oats. Then I fill the container to the top with pure cider vinegar and give it a good stir to distribute the vinegar. Put a lid on it and place it on a shelf for a few days. Check in on it and add vinegar as needed to keep the oats covered as they absorb it. 

Prepare the media by soaking in vinegar as described above and put some in your container to a depth of about 1/2". Too much depth can cause your worms to take longer to start wall crawling. If your oats aren't good and soaked, moisten them with a few spoons of vinegar.

media in container

Your six ounce starter comes in a sealed bag. Snip one corner off the bag, and pipe the starter onto the surface of your media like cake frosting. This is not a good time to show your significant other what you are doing. Use a spoon to spread the media evenly over the surface of your culture.

media in container

Starter placed on medium. Now put it away in a cool spot out of the sun and bright light. Check it in 12 - 24 hours and you should see worms beginning to crawl the walls!

culture complete photo

Keeping your culture going - Pretty simple

Give your newly setup culture a week or so to get going strong. If it seems dry, sprinkle a couple spoons of cider vinegar over it. A couple times a week, stir the surface layer up a bit, but no deeper than 1/4". You don't want to turn the worms too far under. This keeps things aerobic and helps combat spoilage bacteria. The oats will liquefy somewhat over time, but this is no problem for the vinegar eels and is alright. If a cloudy, grayish looking layer develops on the culture's surface, do not panic. It is mother of vinegar which is a mixture of yeast and bacteria. Add a little vinegar and break it up well. As much as 1/8" of vinegar on the surface of the culture is fine too. Repeat as necessary. I've had worms be fine under a thick layer of this mother, and they reappear as it is broken up. A high worm population helps prevent this from forming.

When your culture just starts getting dark, and the smell is just a little more foul than vinegary, it's time to start another one. Start the backup well before your original culture starts looking and smelling really bad. Prepare another container like the first one, and spoon off the top 1/4" of your current culture, using it as a starter for the next. You could also do this when your first culture is going strong, to make sure you have a backup.

If you are outside the US or can't get one of my hyperdense starters

You can start from scratch using a standard liquid vinegar eel starter or culture. It takes about a month, and sometimes doesn't work first try, so patience is needed. Begin by preparing medium as instructed above. Get the medium into a container as above, but use more, filling the container about halway up with media.

Pour your liquid vinegar eel culture into the container until it is about 1/8" higher than the media, so the media is slightly submerged, then close it up, and put it up. After a few days it will develop a skin on top of the liquid. This is mother of vinegar, a combination of bacteria and yeast. Give it a good stir, breaking it up. You should do this at least once a day, twice is better, for the first month. After the culture takes off, the worm activity will keep the skin broken up. If the oats absorb all the excess liquid, top it off with cider vinegar to bring it up to just over the oats.

If you'd rather get going in a few days as opposed to weeks, the starter sold here will do that.

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How To Culture Chlorella vulgaris

What is Chlorella vulgaris?

Chlorella vulgaris is a species of freshwater microalgae. It is best used as a food for cultures of daphnia, moina, rotifers, and other small creatures cultured as live food for aquarium fish. Chlorella is commonly known as green water, and in scientific terms is known as phytoplankton. Daphnia, moina and the other small life forms that feed on Chlorella and other microalgae are known as zooplankton.

Cup of Chlorella

Why Culture Chlorella vulgaris?

If you are planning on culturing daphnia or other zooplankton species, it is a very good idea to culture Chlorella or some other microalgae species first. Research any algae species you want to culture, because not all microalgae is useful as food for zooplankton. When fed to a daphnia or other culture, Chlorella stays alive and even reproduces until it is eaten. Feeding yeast and/or spirulina powder to a daphnia culture instead of live microalgae is tricky and a learned skill. Any leftover can and will decay, fouling the culture water and killing the daphnia. Having a green water culture, like Chlorella, on-hand dramatically increases your chances of success with daphnia and other zooplankton cultures, especially when populations are low right after a culture is started.

Daphnia bucket

What Chlorella vulgaris or any microalgae culture is NOT.

Contrary to popular belief, a pure microalgae culture (green water) is NOT a good first food for tiny fry. Fry will starve out if fed pure Chlorella or other microalgae because the cells are too small for them to see and eat. Chlorella cells are between 2 and 10 microns in diameter. By way of comparison, a brine shrimp nauplii is about 450 microns long. The smallest paramecium (a type of infusoria) is about 50 microns long, and a human red blood cell is about 8 microns in diameter.

The image below is of the postabdominal claw of a Daphnia magna; essentially a daphnia toenail. The little green spheres in the upper left of the image are Chlorella vulgaris cells adhering to the Daphnia. They are about the size of human red blood cells, and this illustrates why Chlorella is great food for Daphnia and other zooplankton, but far too small for fry.

Chlorella on Daphnia

How then do some hobbyists successfully feed fry green water as a first food? It occasionally works because the green water used is not a pure microalgae culture. It is an accidentally combined culture of unknown microalgae species and unknown zooplankton species. Any nourishment the fry get is from the little swimmers, not the algae. These cultures are started by exposing tank water to sunlight or some other light source, and hoping that useful algae cells and zooplankton are in that water and will multiply. It's a dice throw that fails more often than it succeeds. Far better to use proven, reliable methods to culture live foods and feed fry, juveniles, and adult fish.

Green water in outside buckets

Chlorella, or any other microalgae, should always be cultured separately from all other organisms.

When even microscopic zooplankton species get into a green water culture, they generally undergo a population explosion and end up crashing the microalgae culture. Always culture microalgae separately , and feed other cultures by harvesting from the Chlorella culture and adding the green water to the daphnia or other zooplankton cultures being fed.

The following instructions are for getting started in phyto culture using my Chlorella Starter Kit (Item designation CSK).

Kit Materials

  1. Chlorella vulgaris 2 oz. (x2)
  2. Guillard's F2AB 50 ml
  3. 7 ml Pipette (6)

Chlorella Kit

The Starter

These (2) two ounce portions of Chlorella vulgaris are from young, growing cultures. Each can be used to start a two-liter to one-gallon mother/backup culture you can use to start larger production cultures.

The Fertilizer

Phyto cultures require fertilizer. Algae are plant-like organisms with special nutrient requirements. Guillard's F2 is a fertilizer developed to meet the special needs of microalgae. It is a two-part mixture, composed of parts A and B that are kept separate for long-term storage. In addition to minerals and trace elements, it contains vitamins needed by microalgae for optimal growth and development. The bottle provided with the kit is premixed A and B, and the 50 ml. portion is enough to culture about 25 gallons of Chlorella. If you wish to purchase more F2 fertilizer, it is available on Amazon as "Fritz F2 Algae Food." Some hobbyists use Miracle-Gro liquid all purpose plant food with mixed results. I have no experience with this, and the lack of a vitamin component is concerning.

7 ml Pipettes

These pipettes are very useful for measuring fertilizer and transferring/feeding culture. They are one of the most useful things in my fish room. More are available HERE.

Materials You Provide

  1. Suitable Location
  2. Light Source
  3. Culture Container
  4. Dechlorinated Water
  5. Air Supply, Tubing, Valve
Suitable Location

Select a location for your culture(s)that maintains a comfortable room temperature. If you are comfortable, your phyto and zooplankton cultures should do well at that temperature. The location also needs to have an electrical outlet for lights and air, and should be somewhere the light, potential spills, and bubbling sounds won't bother housemates.

Culture shelf

Light Source

The more light the better. I use high output LED shoplights for my production buckets, and Smaller LED strips for smaller spaces. Mount the lights as close to the surface of the cultures as is practical. Fluorescent and special plant bulbs can be used, but they are expensive, have higher power requirements, and may generate unwanted heat.

Primary lights

Culture Container(s)

For smaller backup containers I like to use clear, two-liter soda pop bottles. Store brand is usually $1.00 or less, and you can pour the contents out (don't drink it!) and remove the label to get very useful containers.  Old school, one-gallon glass jars also make great backup containers. High-volume, production cultures are best grown in five-gallon buckets, easily available at any of the larger hardware stores. Thoroughly rinse out whatever container you use, without using soap or any other chemicals, just water. 

Gallon jug of Chlorella

Two culture bottles

Dechlorinated Water

I use tap water dechlorinated with my DIY Sodium Thiosulfate solution. Any dechlorinator works. Chlorella isn't too picky about water parameters. It grows well from pH 6.5 to 8.5 and does very well at my pH of 7.2.

Air Supply

I run the cultures off the central header in my fish room. Cultures can also be aerated using smaller, individual pumps. Standard aquarium silicon tubing and air valves are also needed.

Getting Started

Container Prep - Start Backups

Here I'm using a two-liter soda pop bottle. Prep involves making two holes in the bottle or cap. One hole is for the air line that goes in and to the bottom of the bottle. This is necessary to keep the algae cells in suspension. The other hole is to let the air that's pumped in back out of the bottle. There are a couple ways to do this.

The method used on most of my backups involves drilling two holes in the top: one for an air line that runs to the bottom of the bottle, and another to vent the air out of the bottle. Some rigid tubing, if you have it, makes it easier to get the line all the way to the bottom. You can leave the vent hole open, or put a few inches of air line just barely into the vent hole to prevent even small droplets from splashing out. In the image below the vent hole is just left open.

Bottle with cap holes

A much simpler method is to (carefully) heat up a screwdriver tip and push two holes in the plastic side of the bottle just below the cap. If I had thought about this method when I started experimenting, I would have used it instead of drilling the cap because it is easier and works quite well.

Culture bottle

Measuring Tip: 1 ml of liquid = 20 drops

After the container is prepared, I add dechlorinated water 2/3 of the way up, and one of the two-ounce Chlorella starters. Then I add 1.5 ml of F2AB, and close the bottle. Enough starter is provided to make two of these cultures. If you are using a one gallon jug or other container, the process is the same. I put a loose lid with a notch in it for the air line on the one-gallon jugs. If using a larger container, you can sink the air line by rubber-banding it to a lava-rock, small piece of PVC, or any other inert weight that won't react with the culture. Never use an air stone, and cut the submerged end of the air line on an angle to help prevent clogs.

Culture setup

Important: Be careful to not contaminate your backups with any any other organisms from tanks or any other source, like splashes, wet hands, etc. You want to keep these cultures 100% Chlorella vulgaris.

The culture is placed under lights and air turned on to give a moderate current. This is necessary to keep the Chlorella in suspension. Without air, it settles and the lower layers die off. I use a 16/8 on/off cycled for the lights, roughly paralleling our schedule. Within days you should see progress as the culture(s) get a darker green.

2 liter running

Always run multiple backups just in case.

Production Cultures

Large bucket of Chlorella


To start a production culture, I add four gallons of dechlorinated water to a five gallon bucket, and fertilize with 1.5 ml of F2AB per gallon. Then I seed it with about two liters of mature green water from a backup bottle. I drop in an air line and cover the bucket with a piece of glass (sand the edges!) of a square of plexiglass. Don't forget to restart the backup bottle.

After the bucket starts logarithmic growth and gets a good green tint, I top off with dechlorinated water fertilized to 1.5 ml F2AB per gallon.  

Maintenance and Use

Once the production bucket(s) are up and running you can use a smaller container to dip out Chlorella and feed it to daphnia, moina, and any other zooplankton cultures you are working with. Be careful to always use the same dipper and not contaminate the bucket with tank water that may contain organisms that can crash the culture.

Covered bucket culture

I start harvesting from a culture while it is in the logarithmic growth phase (medium green) and before it turns dark green. After a gallon is removed from the bucket, top it off with dechlorinated water dosed with 2 ml per gallon of F2AB. This dose is slightly higher because the algae population of the culture has to be fed on an ongoing basis. If you are not getting the growth you think you could, you can increase the dose to 2.5 ml per gallon with no bad effect from the increased fertilizer. Once the bucket hits dark green, you must harvest and replace regularly to extend its life by slowing the buildup that accumulates on the bottom as cells sink/die. Depending on your parameters and setup, you should be able to get four to six weeks from a bucket before it needs restarting. As long as you have adequate backups going, feel free to experiment!

If a bucket crashes, the water will largely clear out and the algae fall to the bottom. This is usually caused by a protozoan or metazoan of some kind getting into the culture, or by dead algae building up and decaying. Re-start by dumping the culture, thoroughly scrubbing out the bucket, rinsing with very hot water, then thoroughly drying the bucket before resetting it. The vast majority of contaminating organisms will not survive completely drying out.

That's about it in terms of getting started. Don't be afraid to experiment, and keep your backups going. If you have any questions along the way, you can always drop me a note at:

Chlorella Vulgaris Starter Kit - Cost Combined On Multiple Purchase
Item Price Ship Item Code
Chlorella Kit $10.00 $4.00 CSK

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