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NFC: Moina - Russian Red Daphnia
Here is the article on Mona - Russian Red Daphnia as asked for on the
NFC chat last Sunday night
Moina - Russian Red Daphnia
Moina is also known in the UK as Japanese Daphnia and in the USA as
Russian Red Daphnia. There are in fact several species of Daphnia and
Moina is a very close relative but is much smaller. Another species is
Bosmina and indeed many Moina cultures are in fact Bosmina cultures,
however as both are the same to cultivate and eagerly accepted by all
species of tropical fish it will not matter which species you have.
Moina are a semi-transparent to an off white in color creature with a
thin, flexible and collapsible exoskeleton (carapace) with gills for
breathing underwater. The length of the female body varies from 0.4 mm,
newly hatched to about 1.0 to 1.65 mm adult size. The observed lengths
of the male vary from a newly hatched size of 0.4 mm to an adult size of
0.6 to 1.13 mm.
The parthenogenetic female's body consists of a large head, followed by
the trunk, enclosed in a two-valved carapace and finally the
post-abdomen, slightly protruding posteriorly beyond the carapace. The
head is usually smoothly rounded dorsally with no rostrum. The head
ends behind in a slight depression, the cervical notch which separate it
from the trunk. The single large spherical compound eye is located at
the apex of the head, very near to the anterior edge. It has numerous
round, colorless lenses at its periphery. The ventral lower edge of the
head bears the snout like labrum, dorsal to which is a pair of shout
mandibles. A pair of small maxillae follows and each maxilla is armed
with three strong setae bearing setules. The freely movable antennules
are fairly long. Distally they bear a group of olfactory setae which
are fairly long and of uniform length. The large second antenna which
is the main swimming organ, is a biramous structure with a stout basal
joint form which the two branches arise. The carapace when seen
laterally looks like a lady's purse. When the brood pouch is empty it
has a slightly convex almost straight, dorsal edge. The ventral edge is
more convex. It bears a row of posteriorly directed short setae. The 5
pairs of trunk limbs are enclosed within a ventral "filter chamber" of
the carapace. The post abdomen bears a pair of long abdominal setae.
The anus is not terminal and the conical portion (anal protuberance)
beyond the anus ends in strong anal claws.
The ephippial female differs from the parthenogenetic female by having
the dorsal part of the carapace thickened and modified into an ephippium
containing two resting eggs which are initially positioned side by side,
but which rearrange themselves to lie one behind the other just before
the ephippium is shed.
The male resembles the female in most features except for its smaller
size, shape of head, nature of antennules, structure of one leg, leg
-"A", and the shape of its carapace (exoskeleton). The head is smooth
but drawn out into a sharper cone than the female's. The compound eye
has larger lenses which are concentrated on the anterior edge. The
antennules are much longer and stouter than those of the female and are
more than one-third of the body length. Distally, each bears 6 strong
grasping hooks. The antennule is slightly bent at about one-third of
its length and at this juncture, two lateral unequal setae are found. A
hook and clasper arrangement is developed on leg - "A". The carapace of
the male is more angular than that of the female. The posterior dorsal
edge is slightly drawn out into an acute angle.
There are several advantages of raising Moina as opposed to other
Daphnia varieties. One of the most important is surely the abundance of
proteins. Moina poses the highest protein content, 75% of dry matter,
of all commonly available and cultured critters. Moina consist of 95%
water, 4% protein, 0.54% fat, 0.67% carbohydrates and 0.15% ash. Amino
acids are not stable and usually break down within hours of the death of
the host, Moina in our case. The fatty acid composition of food is
important to the survival and growth of fish fry. Omega-3 highly
saturated acids are essential for many species of fish. Moina cultured
on activated bakers yeast are very high in monoenoic fatty acids. Moina
also provide two primary vitamins that are of vital importance to fish,
vitamins A and D. Vitamin A is essential for the growth and development
of fish, and it also serves as an excellent anti-infective agent.
Vitamin D is primarily responsible for the production of bone, and all
vertebrates are therefore dependent on it. Moina also offer small
amounts of vitamins B and C, which vary in quantity depending on what
foods the Moina have consumed. Vitamin B supports tissue growth and
stimulates appetite. Vitamin C aids in skin formation and coloration.
Resistance to extreme temperatures is another of the several advantages
of raising Moina. Moina will tolerate temperatures of 40 to 95 degrees
Fahrenheit (4 to 35 degrees Celsius). They can withstand swings in the
daily temperature from 41 to 88 degrees Fahrenheit (5 to 31 degrees
Celsius), their optimum temperature range being 42 to 88 degrees
Fahrenheit, (6 to 31 degrees Celsius). In fact one can easily keep
them in the refrigerator for a few days, although the protein levels
will drop substantially during that period. They will be just fine
perhaps a bit hungry. More and more commercial fish hatcheries are
using Moina as opposed to baby brine shrimp.
The genus Daphnia put about 70% of their energy into reproduction and
only 23% into growth. Moina reproduce both by live birth and by eggs
(ephippa) that sink into the mulm. Unfertilized females deposit their
eggs in the brood pouch where they will immediately hatch and develop as
females, a process known as parthenogenesis. In such parthenogenetic
reproduction males are bypassed. Nearly all Moina are born female and
pregnant so a male is not necessary. About every three to five days, a
female Moina will give birth to about ten to twenty babies. Three to
five days later those babies and their mother will be ready to give
Moina have to molt in order to grow. The molting cycle and the egg
cycle are closely tied in with each other. The eggs are laid
immediately after the molt and the young individuals are ready to be
released just before the next molt. At ordinary temperatures, the whole
process takes about three to five days but is speeded up at higher
temperatures. This continues until adverse conditions occur.
When adverse conditions occur some of the hatching eggs instead of
developing into females will develop into males. These males then mate
and fertilize the females which then produce the resting eggs (ephippa).
These eggs are thick shelled and usually 2 are produced at once. The
brood pouch becomes modified in order to receive these eggs. The
structure resembles a saddle and is called the ephippium. When the
mother molts the ephippium is cast off. The ephippium does not
disintegrate, but can remain intact for a long time, surrounding the
eggs which will not complete their development and hatch until favorable
conditions return. In this state the eggs and ephippium are very
resistant and allow the animals to tide over bad spells and to spread
over wide areas. This is nature's insurance policy that the Moina are
not wiped out by fickle weather. These eggs rest during adverse
conditions and when the conditions are suitable, hatch as females and
the whole cycle starts all over again.
This cycle produces what are known as pulses with periods where the
water absolutely teeming with Moina and hardly any at another time.
This happens even in the small containers and the Moina should be
regularly but sensibly harvested to reduce this cycling to a minimum.
Take out or harvest to many Moina and reproduction slows down until a
large female population is built up again. Harvest too few and the food
is soon exhausted and ephippa (resting eggs) are produced instead of
young females. No matter how careful you are, this is bound to happen
so do not worry as the culture will soon pulse again. The Moina culture
can be kept going indefinitely. It is believed that over crowded
populations, shortage of food, too low or too high a temperature, too
short light period or too dim a light, and an excesses of excretory
matter or waste metabolites are the main causes of ephippa (resting
Hatching ephippa (resting eggs): Ephipia are the resting eggs that can
withstand freezing and drying conditions. They are black, saddle-bag
shaped, and pretty hydrophobic, about one (1) to two (2) mm long and
look like specks of pepper, some of which will float on the surface of
the water and others which will sink to the bottom of the culture
container. What is nice is that they will also withstand a three to
five minute sterilizing bath in a 5% Clorox solution, which very few
microorganisms will do. Just rinse them afterwards and put them in some
aquarium water and place in the refrigerator for about two weeks. Fill
a two to ten gallon aquarium with hard alkaline water the same
temperature as the water in the refrigerator. Aerate lightly and add
the ephippa (resting eggs). Allow the water to reach room temperature
naturally and slowly. Once the Moina have hatched, aeration is
optional. Tank should be lit a minimum of 12 hours a day or leave on 24
hours a day. Another hatching method is to place the ephippa (resting
eggs) and a little fine peat moss in a ten gallon tank with less than a
half inch of water. Allow the water to slowly evaporate. After the
tank has been dry for at least a week, completely fill the tank and
lightly aerate. Usually only a few of the eggs will hatch at an
attempt. This is nature's insurance policy that the Moina are not wiped
out by fickle weather. Each time you repeat this processes, a few more
eggs will hatch. No matter what you do, or don't do, a few eggs are
sure to hatch. Almost impossible is it that nothing, other than using
rain water, distilled water, R O water, or deionized water, would make
things go wrong.
The main advantages of Moina are that they can be cultivated all year
round in relatively small containers and they aren't as picky as Daphnia
on water quality. The young are in fact as small or smaller than newly
hatched brine shrimp and of course being freshwater crustaceans they
will live in the fresh water aquarium until they are eaten. Cultivation
is simple, obtain a starter culture of Moina from either another
Aquarist who is maintaining one, likely candidates being Killie keepers,
avid breeders or from a commercial source. However it is quite easy to
start your own starter culture by obtaining Daphnia from a pond or
purchasing a bag of them from your local aquarium shop. These will
normally contain some Moina as well as Daphnia. Pour them through a
fine mesh net and retain only those that pass through the net and
culture as above. Normal Daphnia do not take to well to being cultured
in small containers and will normally not reproduce in quantity, by
observing the culture and re-sieving as necessary you will soon have a
pure Moina culture.
The culture container can be any non toxic vessel of a minimum of about
1 gallon (4 liters). Moina seem to prefer a layer of mulm on the
bottom. This can be either mulm from an aquarium or old well matured
peat moss. Moina do not seem to mind water drawn straight from the tap;
but as with any aquarium venture, tap water used should be treated with
aeration or de-chlor to remove chlorine before the culture is started.
The best source of water is the biologically tempered water from a fish
or plant tank from doing water changes. They thrive in it. Water
should be hard, alkaline with a pH between 6.5 and 9.5, clean and clear.
Rainwater may be too soft and too free of the minerals the Moina need to
build their carapace (exoskeleton). If using rainwater dilute with a
little tap water or add some form of calcium. A nylon filter bag of
crushed coral or crushed oyster shell will raise the dissolved calcium
levels, increase and buffer the pH at a tolerable level but more
importantly it will supply the calcium needed for their carapace.
Without adequate amounts, the Moina will reproduce sexually instead of
asexually, and hence produce ephippia (resting eggs) instead of live
young. In building their carapace the Moina will over time use up or
deplete the available calcium and as you harvest the Moina the calcium
is removed from the system. Even if you use hard water you may want to
add a handful of dolomite lime or crushed coral or oyster shell, a drop
of chelated Fe (iron), a little K (potassium), and Mg (magnesium) to the
culture any way.
Another other requirement is no plant life, any plants growing or a
large quantity of thread algae and the Moina either disappear or
production is severely reduced. The final requirement is good strong
light with a duration of 12 to 24 hours as again production is reduced
or ceases in poor or short light periods. Temperature does not seem so
critical and anywhere between 60 to 88 degrees Fahrenheit (16 to 31
degrees Celsius) will give good results and even lower temperatures do
not slow down production that much. Culturing Moina in a bare 10 gallon
tank will give you enough to feed a bit of Moina to 5 to 7 tanks every
other day. As you set up new and reset older cultures in the future,
use a coarse net to catch only the larger female Moina as brood stock.
This will help eliminate males, which are smaller than the females,
from the culture and speed up production.
Moina are mixotrophic, that is they unselective filter feeders and feed
on wide variety of tiny organisms such as rotifers, paramecium,
bacteria, Euglena, protozoa, yeast as well as any other nutrient or
particle of appropriate size that will stay in suspension long enough to
be eaten. When feeding the Moina culture you are really feeding the
food chain below them as well as directly feeding them. Various
concoctions are used by aquarists to feed Moina cultures. Moina are
cultivated commercially by fish farms (see Singapore Fancy Guppy Culture
Web pages - follow links from the Fancy Guppy Association web site).
Some aquarists use a scaled down version of their method by feeding a
diluted manure concentrate.
Moina can also be used to clear the green water of aquariums and large
outdoor ponds without using dangerous chemicals. In some cases the
Moina may fail to multiply and clear up the green water because the
green water is deficient in nitrogen, and possibly other nutrients. If
this is the case then the algae will not have enough nutrition to allow
the Moina to multiply. Adding a nutrient solution makes the green water
become brighter green, and the Moina will respond to the addition of
nutrients, start multiplying and do the job of clearing the green water.
Theoretically it takes 10 lbs. of Euglena, paramecium, whatever to
produce 1 lb. of Moina. In addition to the following recipes and
feeding methods when doing water changes top off the Moina cultures by
using the water from an established aquarium or plant tank, it will have
food, protozoa, in it your Moina will eat.
Every day to every other day feed one of following:
1. Green water: The easiest and most consistent method for
culturing Green Water / Algae is to use seven one half gallon or one
gallon glass cider jugs as algae culture containers. Sit these algae
culture jugs on a South facing window sill to get the maximum amount of
light. An air pump with a manifold to split off seven air lines for
circulation in the algae culture jugs. This is critical so that algae
doesn't grow and block the sun light on the sides of the jug. Obtain
from either a fish tank or the tap enough water to fill the algae
culture containers. Water from an established aquarium housing fish
that would normally be discarded after a partial water change, provided
it isn't acidic and soft is the best water. Alkaline water with a pH
greater than 6.5 works best. A simple formula for raising the pH and
alkalinity of water is to add 1 level teaspoon of sodium bicarbonate
(baking soda) to 20 gallons of water in order to raise it 0.1 on the pH
scale. Now to the water, to be used in the algae culture containers add
a soluble garden fertilizer (Miracle Grow) at the rate of one tablespoon
per gallon. This fertilized water is used in the algae culture jugs and
this system is then seeded with green water as follows:
1) Seeded algae culture jug #1 with green water;
2) Two days later seed algae culture jug #2 with green water;
3) Two days later seed algae culture jug #3 with green water
As so forth - you get the picture. When algae culture jug #1
has turned bright green (about 7 to 14 days), pour it into a Daphnia
culture tank as food for the little guys. Refill the jug with water
fertilizer mixture and seed with some algae from algae culture jug #2
which should be about to turn bright green. This is repeated with each
of the algae culture jugs as they turn bright green. As you might be
able to tell, this will provide about one half gallon to one gallon of
fresh green water every two days.
Now, a few words of warning:
A) Clean and sterilize each jug after each use to prevent fungus
B) Empty and restart each jug on schedule as it turns bright green
even if you don't need it as food. This will keep the cycle going. If
you don't do this, you end up with everything out of synchronization and
a big dark green mess to boot.
C) If deficient in nitrogen, and possibly other nutrients, the
algae won't have enough nutrition to allow the Moina to multiply.
2. Infusoria: "Infusoria" is a generic term for the microscopic
and near microscopic life found in water. Examples are protozoa,
rotifers, vorticella, protozoa, paramecium, bacteria, Euglena, yeast,
and unicellular algae feeders, etc. To cultivate use a one gallon clear
plastic bottle; two teaspoon of sugar, one quarter to one third of a
quarter ounce (7gram) packet of Fleischmann's Rapid Rise yeast; enough
chopped up lettuce to cover surface, add more lettuce as it decomposes.
Cover container and place in the sun. Keep outside or plan to be
single, if you're married. It stays white, but is more opaque than just
yeast and sugar in water. It smells foul, but the liquor is rich in
yeast, Infusoria, and other critters the daphnia love. Filter some of
the mess through a coffee filter add a couple of ounces to the daphnia,
just enough to begin to cloud the water. Use a bubble wand to keep
water moving. Just add more water and a little lettuce from time to
time to the one gallon plastic bottle to keep the Infusoria going.
3. A Gram flour liquor: To make the liquor mix two to four
tablespoons of gram flour mixed into a smooth paste in one half cup of
water then made up to a pint (½ litter) with water and stirred well.
This mixture can be used straight away and the extra or excess mixture
can be stored and used latter as required. This Gram flour liquor is
added to the cultures until the water in the culture is slightly cloudy
but the bottom of the container can still be seen. The excess mixture
will ferment during the period it is stored hence the name Gram flour
liquor. Normally within a few days the container will contain a cloud
of Moina, some of which can netted out and fed to your fish. If the
water has cleared add several drops more of the Gram flour liquor.
Gram flour used to make onion bargees, sweets savories,
and soups and is available from any Indian food shop. The flour is a
very pale yellow in color and seems to be a cheap, good maintenance and
growth food. Gram flour is made from ground Split Tyson Chick Peas,
Pigeon Peas, Chana Dal, Yellow Peas or Garbanzos Beans from Indian
markets. In India these are called Chana Dall (Dall means Pea). So
Chana flour is the same as Gram Flour. Besan, Farine pois chiche,
Kichererbsenmehl, or Harina de garbanzo are other names for Gram flour.
It should be easy enough to buy dried peas and a mortar and pestle, and
grind a week's worth when you need it. Whole wheat flour, which GRAHAM
crackers are made from, is occasionally refereed to as GRAHAM flour.
4. Gram Flour: Gram flour itself can just be scattered on the
surface if preferred and will produce just as good results.
5. Yeast, Live or Dead: The stuff sold in health food stores as
'brewers yeast' contains nutritious, but > not very tasty, _DEAD_ or
deactivated brewers yeast. The stuff sold in the little packets, like >
Red Star or Fleischmann's and is used to bake bread is LIVE or
activated bakers yeast.
Dead yeast: Feed deactivated brewers yeast just by
sprinkling a little of it on the top of the Daphnia culture container
water a few times each week. The more you feed the more Daphnia you
get, but over feed and the water goes bad.
Live yeast: > > > Two teaspoons of sugar, three
quarters of a teaspoon or one-fourth of a quarter ounce (seven gram)
packet of Fleischmann's Rapid Rise yeast in two cups of warm, 95 to 105
degrees Fahrenheit (35 to 41 degrees Celsius) water. Water warmer than
105 degrees Fahrenheit (41 degrees Celsius) will kill the yeast. When
the yeast, sugar, and water mixture has cooled to room temperature add a
couple ounces of the mixture to the Daphnia culture, just enough to
begin to cloud the water. Be careful about the activated yeast you buy,
it may also contain additives. Additives like calcium sulfate, great if
that was all they added, save on the hard water, however vitamin C or
ascorbic acid is a BIG no no. Basically this kind of product can
drastically changing your pH and water chemistry and kill your Moina
6. Strained baby foods : Sweet Potatoes, Squash, Carrots, Green
Beans, Spinach and Peas. Two ounces, or a heaping tablespoon of
strained baby food mixed into a smooth paste in one half cup of water
then made up to a pint (½ litter) with water and shaken well. This
mixture can be used straight away and the extra or excess mixture can be
stored and used latter as required. This strained baby food liquor is
added to the cultures until the water in the culture is slightly cloudy
but the bottom of the container can still be seen. The excess mixture
will ferment during the period it is stored. The daphnia love it. Only
problem is, the daphnia will match the color of the food and if you
slightly over do the food, making the water the color of the food, they
disappear! Of course, they reappear as the food is eaten.
7. Vegetable Juice Cocktail: The recipe, eight ounces of frozen
peas, two Theragran vitamin pills or any other multivitamin or use a
fish vitamin preparation as directed instead, three ounces of carrots or
beats, about a cup of organic beet tops, and some paprika. Blend the
paprika first before adding all other ingredients. It seems to be too
large a particle to do any good as is and will not micronize when
blended with all the other ingredients. Blend everything until
liquefied and then pour through a fine net and squeeze out as much of
the juice as you can. Combine the juice with enough cold water to make
1 gallon. You can double the recipe to make two (2) gallons of food.
Store covered in the fridge for up to about a week. Always check the
smell before you use it. It's made from veggies, so it will never smell
good, but one sniff will tell you when it's no good. You can make it
last longer by including half a cup of Reef Crystals or other high
calcium artificial saltwater mix. For variety substitute carrots, sweet
potato, spinach, broccoli for the beets or green beans for the peas.
The important thing is one green high protein content veggie, and a
smaller amount of a yellow, red, or simply high carotene content veggie.
Don't add carrot tops or the green marks on a carrot. They contain
tannic acid, bye bye Daphnia! Persimmons, acorns, and oak leaves would
also contain tannic acid. Acidic foods like tomatoes also don't sit
well. This recipe does not freeze well, so make a half or quarter
recipe until you get lots of Daphnia going.
8. Wheat or Rye Flour: You find it in the normal grocery store.
Take a pinch between your thumb and finger and put it in a small glass
of water, mix it up and throw it in the Moina tank. It should just make
it cloudy enough to just see through it.
9. Roti-Rich: It is a liquid green goopy stuff intended for
raising 'micro things, the advertisement is in the back of FAMA. You
keep it in the 'fridge and every day put five to eight drops in the
Moina culture tank. It clouds the tank like the wheat flour and the
next day it's as clear as if there was a filter on the tank.
10. Dried milk, rotting lettuce and the liquids from fermenting seed
11. A diluted manure tea concentrate: Sheep, horse or cow manure or
rabbit droppings soaked in water for several days will make a diluted
manure tea concentrate.
Feeding consists of adding sufficient food stuff to just slightly cloud
the water; but the bottom of the Moina culture container can still be
seen. Too much and the Moina will not be able to clear it all and the
water will foul. If it does not become clear within two to three days,
you are feeding too much. Overfeeding a culture is very easy to do and
almost always results in oxygen deprivation and causes your Moina to
perish. This occurs because dying and decaying foods will suck all the
oxygen out of the culture. Feed too little and production will be
reduced. The quantity is trial and error but you soon learn to judge
the right amount. Usually two or three tablespoons to a ten gallon
culture, no more than will slightly cloud the water for a few hours.
Allow to clear before feeding again. We are talking see through not
crystal clear. Don't worry if you do foul the culture just aerate the
water until it clears and the culture should restart from the ephippa
(resting eggs) in the mulm.
1. Use OLD aquarium tank water from water changes to set up the
Moina culture. Let the gunk settle out and use it for Moina culture.
Moina like the biologically tempered water from a fish or plant tank.
They thrive in it.
2. Every 4 to 6 weeks scrub the sides and bottom of the culture
container with a stiff brush to loosen the scum and accumulated algae,
allow to settle and siphon the gunk off the bottom, then top up the
culture container with old aquarium water saved from a water change.
Allow the gunky water to settle over night. The next day place a light
over the bucket containing the settled gunky water and carefully harvest
the Moina from the top layer of water. You maybe able to harvest for
3. Keep 1 to 3 snails in the Moina culture tank. They will ignore
the ephippa (resting eggs) in the mulm and help out by holding down
algae. They also help with the problem of over feeding by eating the
excess food and their droppings are rich in Infusoria or at least will
encourage it. And to boot if they decide to leave the culture
containers you know that the water is pretty badly polluted and it is
time for a heavy duty water change and to restart the culture.
4. Slight aeration with out an air stone, use a piece of three
sixteenths inch rigid air line tubing placed in the middle or back of
the Moina culture container with two to five bubbles per second to just
barely move the water and keep the food in suspension.
5. The Moina culture container should be lit at least twelve hours
a day, but anything up to 24 hours a day will work. If you provide a
short photo period, they may go dormant anticipating winter.
An 8 x 8 x 10 inch high (20 x 20 x 25 mm) all glass tank on the kitchen
window sill will last for years. It will produce enough Moina to feed
from one to three tanks at a time, three or four days a week. You can
also use plastic bowls and other plastic containers with good results to
boost production when required by taking a starter culture from the
existing Moina culture tank and starting and maintaining several other
The Moina can be harvested by netting with a fine mesh net, siphoning or
even by syringe or meat baster. Live bearer fry can handle adult Moina
but if very small Moina are required to feed egg laying fry then graded
nets or meshes can be used to separate the Moina by size.
>Easiest aquarium plant to grow Algae
>The easiest houseplant to grow Mold
The thdifference between Genius and stupidity
Genius has Limits
Hydra - Get "Clout" and follow directions -- it won't hurt the plants or