Killifish
Immature Nothobranchius palmqvisti Gezani feeding on grindal worms

Grindal worms (Enchytraeus buchholzi) are very easy to keep and breed, and make an excellent food for small to medium fish. A typical harvest will contain numerous larger (up to 1cm) and smaller worms (1mm or smaller) suitable for even tiny fry, and what's more, these worms will live happily underwater without dieing and causing pollution. This is an ideal situation to feed tanks of immature killies. Some individuals of certain species (like Nothobranchius palmqvisti Gezani, above) may outgrow, and ultimately predate on their smaller siblings. Grindal worms provide ample food for fry of all sizes, and unlike artemia, don't all bunch together in one area of the tank. Importantly, all fish get a chance to feed.

All you need to culture grindal worms: oats, media, glass, water
All you need to culture grindal worms: oats, media, glass, water

Grindal worm culture regime

The worms and media are kept in plastic food storage boxes, loosely lidded, with ventilation holes. Each culture is fed and harvested at the same time approximately every 24 hours. Cultures live indoors on the top (warmest) shelf of the fish room all year round. It is important to allow the worms ample ventilation; cultures with no air can crash very quickly, however they should not be allowed to dry out.

The traditional culture media for grindal worms is much the same as for white worms: a blend of coir (45%), peat/compost (45%), a small amount of sand (10%), maybe a handful of lime to maintain alkalinity. Cultures will turn acidic eventually and should either be replaced with new cultures if production drops, or partially replaced continuously (I take a few handfuls of media to a fish auction every now and again, and then top up the old culture). Activated carbon can be added to the media. The media should always be damp, yet never waterlogged or sodden.

Another method for housing grindal worms, and one that works very well indeed, is to keep the worms in damp sponge. Simply cut a rectangle of open-pored sponge, maybe three to four centimetres thick, and place it in half a centimetre depth of water in the food storage box. This is the perfect media for grindal worms, maintaining the correct humidity, and providing a huge area for the worms to inhabit. The sponge may need to be rinsed out periodically, especially if production drops.

A typical grindal worm culture
A typical grindal worm culture
The worms gather on the glass in large numbers
The worms gather on the glass in large numbers
The worms can be simply rinsed off
The worms can be simply rinsed off

Feeding grindal worms

Whichever media the worms are kept in, they are fed the same way: on (under) glass plates. I sprinkle a light layer of fine instant oat cereal on the damp glass, and place face down on the culture. Keeping the food on the glass keeps the culture fresh, minimises mold and mites, and draws the worms to the glass for easy harvesting.

The worms are collected 24 hours later, simply by running clean water over the glass. The glass can then again be reloaded with food.

Grindal worm culturing problems

These really are one of the easiest livefoods available for killifish keepers. Provided cultures are kept warm and well fed they can provide daily worms for months with no real problems. Cultures should be restarted when production drops off. Many people complain about mites within their cultures, and moth balls can be used, however if the food is under a large enough piece of glass this is rarely a problem. In fact mites can act as an additional food source for surface feeding killies.

Feeding grindal worms to killifish

Grindal worms make a superb food for most small and medium sized killifish. Quicker growing annual fish such as Nothobranchius will take grindal worms fairly quickly after artemia, often within their first week. Make sure you feed very small numbers if you have a substrate in your tank, as worms will bury themselves, eventually dieing under the gravel. As is the case with white worms, apple and rams-horn snails will eat grindal worms given the opportunity.

10 day old Nothobranchius furzeri eating grindal worms

10 day old Nothobranchius furzeri eating grindal worms This is a still from a short video clip. Click the the image to go to youtube and play the clip. Note there is a high resolution version (just below the image on youtube, look for the 'watch in high quality' link)


Grindal worm cultures for sale

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2 Grindal worm cultures in 8OZ Cup 1 Week Old And 1 Fresh Culture.

Dunn, North Carolina, 283**, UNITED STATES OF AMERICA

$40

Get ready to give your fish the best diet with 2 Grindal worm cultures in an 8OZ cup. These cultures are perfect for all water types. They are live and fresh, perfect for giving your fish the nutrients they need to stay healthy and happy.

This bundle comes with one week old culture and one fresh culture, so you can keep your fish fed for longer. These cultures are made in the United States and have not been modified in any way. They come in a custom bundle with no additional items, ... more

2 oz Grindal Worm Starter Culture LIVE Fish Food Betta Killifish Guppies Mollies

Minneapolis, Minnesota, 554**, UNITED STATES OF AMERICA

$20

This is a 2 oz starter culture of live Grindal Worms, perfect for feeding your tropical fish. Made by Tropical, this high-quality fish food is suitable for a variety of fish, including Betta, Killifish, Guppies, and Mollies. The worms are sustainably raised on bread, scrap vegetables, and fish flakes in the Midwestern United States. They come in a 2 oz container, packaged safely with a bit of food to sustain them during travel
The photos here are of the original colony that I will select ... more

4 oz Grindal worms Starter culture if you buy two I'll give you one for free

Ogden, Kansas, 665**, UNITED STATES OF AMERICA

$17

We do not ship to Hawaii, Alaska, Guam or Puerto Rico, 4 OZ Grindal worms Starter culture Comes in a 12 ounce plastic containerif you buy two I'll give you one for free total 3
friend the worm when you receive it you only put a small ball of food
and as the worm multiplies another ball of food is added
If you throw a lot of food to the worms, the food that they don't eat is damaged and that kills the oxygen of the earth and they die the wormsI only recommend feeding them as they ... more

Grindal Worms Live 16oz Starter Culture

Clearfield, Utah, 840**, UNITED STATES OF AMERICA

$20

We are back with a variety of live food for newly hatched fry to adult fish
16oz Starter Culture!! 
NO MITES OR SPRINGTAILS!!!!
Grindal Worms (Enchytraeus Buchholzi) related to white worms and red worms are white in color, non-parasitic, and can reach a maximum length of ½ inches. Due to their small size, they can be fed to a few weeks old fry to medium-sized fish
These worms are cultured in 100% organic soilless, peat moss free, and sterilized medium. No mites, ... more

2 oz Grindal worm starter culture LIVE fish food for betta fry killifish & more

Ardenvoir, Washington, 988**, UNITED STATES OF AMERICA

$13

Grindal worms are small cousins to earthworms, and appeal to many species of fish, and fish fry, and are very easy to raise! You will receive a 2 oz portion cup of soil less media filled with live grindal worms, as well as detailed instructions to get your colony going and reproducing quickly. Also check out our other live fish food items, as well as heirloom seeds for the gardener in you!... more