Of all the live foods, probably the easiest to culture is the vinegar eel. It is so easy it is easy to forget about them which isnâ€™t a bad thing if it isnâ€™t too long.
The easiest and most productive way to culture these tiny things is to take a large glass or plastic, preferred for obvious reasons, with an opening about 3 inches across. It is not know why it works better to have a wide opening but is assumed to be for air needs. Fill Â½ of the container with apple cider vinegar and the other half with distilled water. Add Â¼ of an apple, peeled if you want to, cubed and you have your culture. Make sure the temperature is the same as your starter culture and put it in the container. If the lid is tight fitting, it is best to drill the smallest holes you can in the lid to allow for some air exchange. Again it is unknown why it helps but it really does. If the lid doesnâ€™t fit tightly, then simply place it on the container loosely and that seems to be enough.
To harvest these little buggers there is a lot of different techniques out there but none as effective as this, as far as I have found. Take a large test tube, 1-1.5 inch Dia. and 4 inches long if you can find it or larger. Smaller will work but the harvest will be much less. Take a small pipette or small baster and siphon off enough to Â½ fill the test tube. Insert enough filter floss into the test tube that it completely blocks the tube, just above the culture media. About the size of a golf ball unpacked is about the right amount. Fill the rest of the tube with fresh dechlorinated or distilled water and let it sit for about 2 hours. In this time, the â€œeelsâ€™ will have made their way to the fresh water and you can siphon them off to feed to your fish and fry. If there appears to be a large number still in the bottom, simply add more water and wait another 2-6 hours. After 24 hours, there should be very few eels left in the bottom and you are ready to start a new harvest.
In order to have enough eels for a large number of fry, 7-10 cultures need to be maintained as although they do grow into rather large population in 4-6 weeks, they can be depleted very quickly as they thrive in the upper part of the culture and very few live in the lower. If you only harvest 3-5 times a week then 2-3 cultures should enough to maintain enough to feed them off for a long time. Cultures can last for a very long time although if you are not harvesting it is best to start new ones every 6 months or so just in case on crashes from overpopulation.