Feeding guppy fry (and other livebearers): the guide to live food

Guppy, platy, molly, or swordtail fry are small at birth... but already hungry! To grow well, they need rich, live food suited to the size of their mouths. Yet, many aquarium keepers (myself included) limit themselves to industrial powders or brine shrimp nauplii. However, these are not truly ideal…

 

The limits of brine shrimp for livebearer fry

Brine shrimp (Artemia salina) are marine crustaceans. Their eggs are fairly easy to find commercially, but their hatching requires salt, warmth, aeration, and some equipment. Practically impossible in an apartment, bulky, messy, noisy… Most importantly, their salinity does not match the natural environment of guppies and other freshwater fish.

Finally, brine shrimp nauplii are often a bit too large for the very first days of fry life, which struggle to catch them. The result: some food remains uneaten, pollutes the water, and the weaker fry weaken in this soiled environment.

 

Microworms: the perfect food from birth

Microworms (Panagrellus redivivus) are tiny white worms, almost invisible to the naked eye (at least to mine!). Unlike brine shrimp, they are not salty and wriggle a lot, but without moving away: fry can easily catch them. Especially since their slender, elongated shape fits perfectly with their very small mouths!

Rich in proteins and complete in essential amino acids and fatty acids, they make an ideal live food for the first 10 to 15 days. Their culture is extremely practical: little space, a nourishing substrate, a few drops of water… and you have a fresh food source for weeks.

 

For this, Aquazolla offers the ZollaBox Baby: a complete kit allowing you to raise your live microworms at home, without odors and taking no more space than a simple glass of water!
Refills let you maintain this simple and productive culture continuously with just one ZollaBox Baby.

Vinegar eels: an alternative for the very first days

Even thinner than microworms, the vinegar eels suit freshly born or very small fry. They swim freely in fresh water and can thus be swallowed effortlessly.
They perfectly complement microworms, especially if you want to vary the diet from the first hours of life.

These worms are so tiny they are even given to egg-laying fry!
Very easy to raise but a bit harder to harvest, Aquazolla even offers pre-filtered, ready-to-use doses, in case an unexpected birth requires it!

Grindal worms: perfect for growth

After about ten to fifteen days depending on the species, your fry can swallow larger prey. It’s time to introduce Grindal worms (Enchytraeus buchholzi): even more nutritious and especially a bit bigger, they promote rapid growth and harmonious development.
Their constant movement mainly stimulates the hunting instinct of young fish in full development, while avoiding the inevitable pollution linked to inert foods.

 

To raise them easily at home, there is the ZollaBox Poisson S: it contains everything needed to maintain your own Grindal worm culture, including the worm strain, substrate, food, and a complete guide in French.

And after? Daphnia and company…

As soon as your fish reach 1 cm, you can introduce more active prey: small Daphnia, ostracods… all help diversify their diet and strengthen their natural defenses like no industrial or artificial food ever could.

 

An aquarium where live food circulates is a healthy aquarium: fish hunt, move actively, and grow strong. Nothing matches this form of feeding for the well-being and vitality of your guppies.
The ideal would be a fry tank, without adults, full of critters like Daphnia and ostracods for example. The fry would grow up among the critters, eating at their own pace, day by day, those that fit their size and letting the others continue to reproduce. Unlimited fry food that never rots at the bottom of the tank!

In summary

Approximate age of fry	Recommended live food	Recommended culture
0 to 3 days	Vinegar eels	Home culture (simple jar + vinegar + water + apple)
0 to 15 days	Microworms	ZollaBox Baby
15 days to 1 month	Grindal worms	ZollaBox Poisson S
Over 1 month	Daphnia, ostracods...	Outdoors, separate tank or with fry

 

Aquazolla tip: live foods improve not only growth but also fish behavior and breeding. Try to introduce some even in small amounts, a little each day, rather than one or two large dry, artificial, industrial meals!

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