Live infusoria, Grindal, earthworms, Microworms and pond Invertebrates

Microworms
Microworms are very small and easily cultured food for smaller fish and fish fry. They are diminutive, only 1-3mm in size. Still even 5cm long fish usually eat them vigorously. Microworm culture smells like vomit.

Microworms sink slowly to the bottom of the tank.

Instructions for raising Microworms

1. Put a thin (less than 1cm) layer of oatmeal in a plastic box.
2. Moisturize with water and a dash of milk. The culture must be pretty moist.
3. Put a tiny amount of dry yeast on the surface and add the starting culture.
4. Make tiny holes to the lid and put it on.
5. Storage in a warm place, however not over 28 Celsius.
6. Microworms start to crawl in a few days. They can be fed directly from the sides of the box, but the filtration must be turned off.
7. Start a new culture when the production decreases. It is advisable to keep multiple cultures.

An ice cream box is a good choise for raising worms.

Microworms crawl on the sides.

Here you can see microworms with a 3cm long aquarium fish
(Nothobranchius furzeri female).

A group of Dwarf Cories (Corydoas hastatus) is chasing Microworms.

Grondal worms or Whiteworms

Grindal worms come in many forms. Some of them are quite big and can not be fed to smaller fish (less than 2cm).

Instructions for raising Grindal worms

1. Put a thick (about 4cm) layer of black soil, peat or moss in a plastic box.
2. Moisturize with water and add some dry cat food. The culture must be pretty moist.
3. Add the starting culture.
4. Make tiny holes to the lid and put it on.
5. Storage in a warm place, however not over 25 Celsius.
6. Grindal worms start to crawl in a few days. They can be collected by adding a plastic or glass plate on the culture.
7. Start a new culture when the production decreases. Remove any mold. It is advisable to keep multiple cultures.

Grindal worms sink quite fast to the bottom of the tank.

A Grindal worm culture with dry cat food added. 

These Grindal worms are 2-3cm long and they tend to hide, when in light.

Sometimes Grindal Worm culture is infected by tiny mites or mold. This has a dramatic effect on the productivity of your worm box. Once infected it is advisable to start a new culture with only a few cleaned worms. In this microscopic video you can see both mites and mold with Grindal worms.

N. furzeri female eats a Grindal worm.

C. gossei and  other corydoras species love small worms.

Earthworms
Earthworms are considered as delicacy in some human cuisines, so it may not be surprising that fish love them too. They can be found easily. They are dirty for sure but can be easily rinsed in fresh tap water. Another way is to put them in a container full of fresh moss for a couple of days. Depending on the size of the fish earthworms must be chopped.

NUTRITIONAL VALUES per dry weight
Protein 62,2%
Fat 17,7%
Calcium 1,72%
Phosphorous 0,9%

Earthworms come in many sizes. Usually you must chop them to pieces before feeding.

Bigger Corydoradinae species (here Brochis splendens) can easily crush earthworms into tiny pieces.

Nothobranchius species have sharp teeth which help them to beat bigger worm pieces.
Here is N. hassoni Bunkeya DC 13-8 male.

Pond Invertebrates

In tiny ponds an aquarist can find amazing variety of good fish food. Even in northern countries ponds can sustain a wide variety of invertebrates. Most common of these belong to the group of Cladocera, more commonly known as water fleas. Water fleas are usually very tiny measuring only about single millimetre. They swim in a twitching style almost solely in the surface. Due to their diminutive size only smaller fish consider them as food.

Another good find in a pond can be mosquito larvae (Culidicae). These are also surface animals. They hang on the surface upside down and when disturbed larvae swims to the bottom of the pond. When collecting any live food in the nature one must be sure that the pond does not have any fish in it. This is very important rule because among the wild fish parasites are common. You must also rinse your findings before pouring them into your fish tank.

A group of water fleas in the water surface. Their size is under one millimetre.

Mosquito larva hanging on the water surface.
This specimen is 7 mm long.

This is so called artificial mosquito larvae incubator. Its water content is about 50 litres.
It is utmost important to put some dirt on the bottom.

Above described cauldron produces substantial amount of fish food every day.
After two minutes of collecting one can have many hundreds of mosquito larvae.
The catching is best to be performed with an Artemia sieve.

Pond animals can be collected simply by a sieve and a bucket.
This sieve is originally a purpose built Artemia sieve.

Two Nothobranchius hassoni males competing for a common housefly.

N. hassoni male is about to catch a winged ant.

Infusoria

Infusoria is a collective term for many microscopic aquaric creatures. Thanks to their diminutive size they are used as a first food for very small fish fry. Infusoria is very easily raised. Some hobbyists use inner side of a banana skin, some buy commercial products. Infusoria is raised in water. Infusoria culture is developed in 1-2 days when kept in light at room temperature. Cloudiness of the culture is a sign of readiness and a hobbyist can take some of the water (a few spoonfuls) and put it in the raising tank.

Although some Nothobranchius babies can eat Artemia from the very start, some may not. Thus it is imperative to offer some smaller food too, like infusoria. Here are Nothobranchius hassoni (10 hours old).

Hobby Protogen is a product of  a German company Dohse Aquaristik GmbH & Co. KG (founded in 1949).
With this is Infusoria farming very easy.

Cloudy water is added to the raising tank in small portions.