Vinegar Eels (Turbatrix Aceti) Today, I want to write a short post on how you can culture and grow a cheap and easy source of live food for newly hatched fry. They are perfect for the smallest fry that may be too tiny to eat newly hatched brine shrimp and for species that will not eat liquifry or other non-living food at first. Fish that fall into one or both of these categories include beta splendens, most gourami fry, some corydoras, killifish, and some small tetras to name a few. Ideally, these fish should be fed infusoria which can be prepared a couple of weeks ahead of a planned spawning. But in cases of accidental spawning or in cases where you want to provide a stepping stone between infusoria and brine shrimp, vinegar eels are perfect. Before I tell you how to make a culture, let me tell you what they are. Vinegar eels are a kind of roundworm also known as nematodes. They are non-parasitic and live in extremely acid environments. Most frequently, you can find them in bottles of apple or rice vinegar…generally the red vinegars are the most likely places to find them. If you go into your cupboards now and pull out an old botle of vinegar, you can hold it up to the light, close one eye, and look into it carefully. If you are lucky (?) you will see very, very small, almost transparent, worms thrashing in a figure-8 pattern. If you see them, congratulation! You’ve got vinegar eels! Incidentally, be careful who you tell this to. After reading about vinegar eels when I was about 8, I checked the bottle in my mother’s pantry and, upon spotting the worms, I excitedly showed them to her. She was not as impressed as I was and she threw the bottle away.
Anyway, you can start a culture by pouring the vinegar into an old jam jar. Add a couple of slices of apple without the peel into the jar. You can leave the cover off or just put it on loosely to allow air exchange. The next step is to forget about it and allow the little roundworms time to multiply. When you need them you can use an eyedropper to collect some worms. You cannot get vinegar into your fish tanks, so put them into a fine mesh net like you buy for baby brine shrimp and help the vinegar drip out by touching the bottom of the net into a dish of fresh water. Then just add them to your tank of fry.
The benefits? Vinegar eels wiggle widely whenever they want to move which draws the attention of newly hatched fish and triggers feeding response. They are easier for the fish to capture than rotifers and, unlike microworms, they will live up to a week in freshwater. Also, your culture jar can be left aline for up to two years without maintenance..and the only maintenance really needed are fresh apple slices and maybe a little more vinegar to replace what evaporated. The drawbacks? They are not meant to be a longterm food source. They do not have as much nutritional content as brine shrimp and are only meant to be fed for about a week until the fish can take newly hatched brine shrimp. Another drawback is that growing worms in a jar of vinegar somewhere in your house will not endear you to your spouse/parent/partner/roommates. Keep the jar hidden!