This is one that might make the stomach of the squeamish turn but is a neat live food for your fish.
The best advice is to use the media sold by the one that you buy the flies from. The media will have mold inhibitor already in it and is a lot easier to use. It is also probably the best media to use. There are many recipes for media and I will list some of them at the end.
First, you need some empty 16 ounce soda bottles, wide mouth mason jars or other similar sizes containers. Once you get into culturing them, you will find what works best for you as far as size and shape. Mix the media according to the instruction given from the seller. Once it has cooled it is ready for your fruit flies. Simply add the fruit flies and let them do the rest. Some kind of material in the container for the flies to climb on seems to help in production. Common materials are excelsior, cardboard tubes, plastic canvas and anything else that allows them to climb on and get out of the media. I am working on a design for a â€œhatcheryâ€ of sorts but it a ways away from production.
Harvesting is not so easy but once you get the hang of it you can do it fairly easily without much problem and few escapees. Tap the container to get them off the top then remove the lid. Tip the container so that the top is a little below the bottom and tap again to get the flies into the receiving container. This can be any bowl, cup or similar container that you want to use. Tap the edges to keep the flies in the container until you open your fish tank and dump a few in. Surprisingly the flies were readily eaten by swords, platys, neons and almost any other fish that will eat off the surface. Make sure there is nothing floating in the tank or the flies can climb on it and escape and possibly make the spouse mad if they find the flies in the fruit bowl! Other than that, escapees are not a worry because they donâ€™t fly and wonâ€™t have much of a chance to get anywhere they can become a real nuisance.
Home made recipes: Instead of listing them, I figured it was better to give sites to look over and read more information about this neat live food. Recipes Media and flies