Some fish need to feed on living organisms to survive; others need it during the breeding season. Raising mosquito or gnat larvae for this purpose is free, easy and requires minimal effort. After checking that doing so does not violate any local laws or regulations regarding public health, all you will need is a bucket, water and some sunshine.
Steps
Step 1. Find a plastic bucket or barrel
A 20-liter bucket will do, as will a 200-liter bucket. You can get 30-40 maggots per day from a 130-liter bucket. A black bucket will heat up faster, but it may also get too hot during the summer season. When the ambient temperature exceeds 27 ° C, move to a place where it will stay in the shade all day. Indirect sunlight will still be sufficient to allow the algae to grow. In fact, algae are the main food source of the larvae. Alternatively, you can use a 20-40-gallon tank so you can see the larvae and also be able to reach those that have burrowed at the bottom. An acrylic aquarium will be more suitable for outdoor use.
Step 2. Place the bucket outside and give it time to fill with rainwater
Or, if it's winter, fill it with snow that will melt when warmer temperatures arrive. If you fill it with water taken from the hose used for watering in the garden, be sure to use a product to remove chlorine and chloramines. The chlorine would hinder the formation of algae, depriving the larvae of food.
Step 3. Place the bucket in the sun
Doing so will heat the water and allow the algae to grow. The ideal result would be to obtain water that looks like green pea soup. The algae that grow on the walls of the bucket are not what the larvae feed on. They need algae that can make the water green
Step 4. Wait until gnats or mosquitoes have laid small clusters of dark brown eggs (the size of sesame seeds) on the surface of the water
If you can find the small oval shaped heap similar to that of a football, you've got bingo! Place it in your tank and the fish will eat the larvae as soon as the eggs hatch, usually within 48 hours. If you don't move them around the aquarium, the eggs will hatch and the larvae will grow by feeding on algae. As they grow, the larvae will take on the shape of a comma and two small antennae will grow. When they have reached this shape, be sure to feed them to your fish.
Remember, insects go from eggs to larvae to pupae and eventually to flying adults. Whatever happens, do not let them reach the adult stage and fly, since midges and mosquitoes are not only annoying, but they can also transmit diseases and infections to animals and humans. See the "Warnings" section for more information.
Step 5. Collect the larvae with a net every 2-3 days to prevent them from evolving into pupae (and then into midges or mosquitoes)
The warmer the climate, the faster they will develop. While you're at it, check other sources of standing water where grubs may be developing (old tires, puddles, unfiltered fish ponds, empty flowerpots, saucers, and any other items that may contain standing water for more than 2-3 days). Collect the larvae and spill the water so the mosquitoes can't settle in your bucket. See the "Warnings" section.
- Use a brine shrimp net. The meshes of these nets are very thin, they seem to be made of the same material as the t-shirts. A normal fish net would not work as well, since the larvae would pass through it.
- Use one or more buckets (one empty and the others full of water and mosquitoes). Place the screen over the empty bucket, and flip the full buckets into the vacuum using the screen as a filter. All the larvae of a certain size will remain trapped in the net and can be fed to your fish. The smaller ones, on the other hand, will be able to cross the net and will be able to continue growing in the new bucket. Using this method, you will need to collect the larvae at least every other day, even if that day you are very tired or don't feel like it, otherwise the larvae left to grow could turn into pupae and from there into adult midges or mosquitoes.
Advice
- Sometimes you will find small hollow shells of the same shape as the larvae on the surface of the water. It is their old skin. These are not dead larvae. Simply, the larvae, like all other insects, moult.
- If you'd rather not breed mosquito larvae yourself, ask your pet shop. There are usually commercially available jars of dried gnat larvae. Avoid them coming into contact with your skin, as they could cause allergic reactions. Rather, handle them using tweezers or flip them some in your aquarium or pond.
- Adult mosquitoes and midges are very similar, and this also applies to their respective larvae. You need a microscope and an experienced biologist to tell them apart. Some gnat larvae will float, just like those of mosquitoes, while others are red and will settle to the bottom of the bucket.
Warnings
- Make sure you collect the larvae every day to limit their numbers. Make sure to always collect any pupae, as they will become adult individuals within 48 hours.
- In some countries it is not allowed to breed larvae, especially in Southeast Asia. Nations like Singapore and Malaysia have very strict laws regarding mosquito breeding, and any violations are sanctioned quite severely.
- Use a clean or new food-grade bucket. Do not use one that has contained paint, tar or other chemicals, as these substances will poison the algae and larvae. Even cleaning them, traces of certain substances would still remain.
- Be responsible. Allowing mosquitoes and midges to become adults would endanger you, your family, your neighbors, your pets and wildlife. Here are some threats to know (and avoid):
- Encephalitis: human
- West Nile virus: humans, horses, birds and other animals
- Malaria: Humans (Anophles mosquitoes, vectors of Malaria, are common in North America and other parts of the world)
- Heart worm: cats and dogs
