Which natural food should you choose for your fish?
How to make the right choice?
Natural food is far superior to industrial foods for our fish.
But once you know that, you still have to choose which creature will be the best or easiest to raise to change the daily life of our wards…
Should you opt for Daphnia, Blackworm, enchytraeids, Grindal worm?…
Apart from the smaller species mainly intended for fry, such as vinegar eels, micro worms, or even springtails, we already have a good choice of fairly large creatures, suitable for almost all our aquarium fish.
Not everyone has the desire or space to start all types of breeding, so on what criteria should you choose the best species to cultivate at home?
Of course, there is the nutritional criterion, and the attraction of our fish to one creature or another. But the ease and productivity of breeding also matter.
To give you all the keys, I will try to detail the strengths of the main species appreciated by fish and accessible to the amateur aquarist.
They are crustaceans. The nutritional composition of daphnia varies greatly depending on what they eat! For example, the protein content of daphnia can range from 40 to 70%, partly due to their diet, but also depending on the oxygen level in the environment. Indeed, they can multiply their hemoglobin level by 13 if needed!
Let's say that Daphnia generally contain 60% protein (on a dry matter basis, of course).
Their fat content is sometimes high (11... to 27%), making it a rich food, as fats are important in the metabolism of aquatic animals.
As it is a shrimp, it is covered with a thin shell made of chitin. Chitin is not digested (like fiber for humans) and is therefore very useful for goldfish. Indeed, the goldfish has a particular digestive system that requires "ballast" provided by plants (fiber) or by crustaceans and insects (chitin).
Springtails are therefore the ideal food for the least carnivorous fish, such as goldfish, xiphos, platys, etc.
Breeding springtails requires some space: at least 10 liters (a bucket for example) preferably near a window or outdoors if the weather is nice. 18 to 20°C is the ideal temperature.
Feeding is simple with fresh live plankton or pure spirulina. The imperative rule is to feed little but often. Especially with dry powders which must be consumed quickly and not pollute the water.
In short, raising your springtails yourself requires having a small tank or bucket and regularly monitoring the cleanliness of the environment.
However, there is an excellent basic food available all year round, fish being extremely attracted by the jerky, almost bouncing swimming of this planktonic crustacean.
Springtails are to freshwater what Artemia is to seawater.
Blackworm (Lumbriculus variegatus) are related to earthworms and thus belong to the world of annelid worms. It is a fairly balanced food for fish, containing 65% protein and 12% fat. A kind of ideal mix.
Unlike Tubifex, this worm is not polluted and therefore does not pose health problems for fish.
Raising this very beautiful reddish-brown worm yourself is possible. The same conditions as springtails apply: a container of at least 10 liters at 18-20°C.
But this worm also needs a substrate to partially bury itself in. Sand is perfect, even a simple well-washed masonry sand.
And above all, the most important: Blackworm needs oxygen, otherwise it dies. A bubbler is therefore essential.
Feeding it is simple: pure micronized spirulina (ideal size for its tiny mouth), or dead plant fragments (cooked vegetables) on which bacteria it consumes will develop. Any excess food given risks rotting and depriving the water of oxygen (hence the importance of the bubbler).
It is an interesting culture, producing quality worms, but a little less productive in quantity than Daphnia.
Enchytraeids and Grindal worms
I grouped them because these cultures are quite comparable.
The difference between enchytraeids and Grindal worms is mainly their size. They are really very close cousins, since both species belong to the same genus Enchytraeus.
The enchytraeid is a fairly large white worm suitable only for adult fish, whereas the Grindal worm is small enough to feed juvenile fish or small species (guppies, tetras, etc.).
For the rest, they have exactly the same nutritional value.
Contrary to a persistent legend, these worms are not fatty. They are even, with only 14% lipids, a little less fatty than daphnia!
On the other hand, their protein content is among the highest, with 70%...
Their nutritional contribution is therefore of high quality and very appreciable, especially since they are clearly very appreciated by fish.
Last point: their astonishing richness in vitamin A and carotene.
Above all, their breeding requires little space and little care.
The enchytraeids are content with a pot containing a substrate (potting soil and a little sand can suffice), with a lid to prevent fungus gnats from invading them. Keeping the substrate moist and cool (below 18°C if possible) is enough for their happiness. Some feed them oat flakes, others banana peels: they are not too picky and can sometimes be found in our garden compost piles! It’s really simple and not demanding. And the breeding can last several years.
To simply and cleanly breed enchytraeids, the easiest is to turn to the Zollabox Fish L, a complete kit including the pot, the worms, the special enchytraeid food, all the equipment, and a complete and clear manual.
As for Grindal worm, a simple container that has held margarine, butter, or an ice cream tray is enough! Hard to get more compact... The substrate is commonly composed of sphagnum.
The lid, as for the enchytraeids, is necessary to prevent parasites or drying out.
For more ease and success in breeding Grindal worms, simply order the Zollabox Fish S, a complete kit that contains all the necessary equipment, the food, the strain, and especially a complete step-by-step manual.
The Grindal worm does not like light: some therefore store the breeding box in a drawer or cupboard, or even under the aquarium.
The Grindal worm takes a long time to start (count a few weeks), but then it is a very regular production of small worms suitable for all fish sizes!
It is generally unnecessary to restart the culture before a good year.
Personally, I obviously have these 4 breeds at home. This allows me to vary my fish menus infinitely (variety is important for them), but above all to never run out: if one breed produces less for a few weeks, another replaces it.
We are far from the monotony of industrial glitter!
Mattier, May 12, 2023