Live Foods - Grindal Worms

Author: Rob Torrens

These are basically miniature white worms, they were first isolated by a Mrs Grindal from a white worm culture. Their size means that that they are ideal for feeding to fish with a small adult size or to larger fry that need something bigger than microworms. They are more temperature tolerant than white worms and should be kept at room temperature.

There are a number of culture mediums used to culture these worms including vermiculite and peat. I have had good success just using commercial compost. I usually set up a culture in a shallow tray (surface area is more important than depth), place some of the compost in the bottom and then sieve over a layer of compost (to get a fine flat surface - the reason should become clear later in the article). You should make sure that the compost is damp, almost wet (the worms definitely don't like a dry culture). Now seed the culture with some Grindal worms.

Feeding of the Grindal worms is easy - they'll eat damp cat cookies, small lumps of porridge or bits of damp bread. You will find that as the worms eat the food you've given them a mound of worms will build up where the food was, it is then easy to get a plastic fork or spoon to remove the clump of worms. This is the reason for having the flat surface, you want to be able to just remove the clump of worms from the surface, you don't want to be digging out bits of the compost.

Another possible way of harvesting the worms is to put a piece glass or flat plastic on top of the culture. The worms coming to the surface will stick to the glass and you can then rinse them off into the tank.

I've found Grindal worms to be very tolerant of neglect, providing the culture remains moist.

You may find that the culture will eventually become infected with mites or midges. While these don't seem to directly harm the worms, they do compete for food and can get annoying. This is probably a good time to start a new culture. If you have an old culture and the worms don't seem to be doing so well, you may want to start a new culture or try sprinkling a small amount of garden lime over the culture (as the culture ages it becomes acidic, the lime counteracts this).