What causes drain flies? Stagnant pools of water, particularly in pipes and other drainage areas, attract drain flies. These small, gnat-like insects feed on and breed in sewage. Organic material can build up along the side of drains quickly, welcoming drain flies to eat and reproduce.
What Causes Drain Flies? Drain flies thrive in stagnant and standing water. Common sources include slow or clogged drains, rarely used and unused toilets, refrigerator drain pans, and standing water created by leaking pipes. They typically enter buildings through basements, windows, and drains.
Once you've wiped out their breeding ground, the adults will eventually disappear because there is nowhere left for them to deposit their eggs.
Identifying the Source
For the plastic cup method, lightly coat the inside of the cup with vegetable oil or petroleum jelly then invert the cup over a drain where you suspect flies may live. Leave the cup in place for several days, but check it daily.
These pests are a nuisance because they infest in large numbers. Once inside, drain flies may plug pipes and spread bacteria from the filth they live in, possibly contaminating food in the process. These pests, even though they live in filth, are not known to spread any disease to humans.
The larval stage of drain flies lasts up to 24 days, while the pupal stage lasts between 1 and 2 days at most. The larvae feed on bacteria, fungi, and other microorganisms that develop in the breeding medium in drains, standing water, and even sewage treatment beds.
A cup of household bleach is generally more than sufficient to kill most drain flies, and all you need to do is pour it down the affected drain.
Adult flies emerge from the breeding sites but may remain nearby. Drain fly control often fails because people don't realize just how resistant the scum and the larvae are to boiling water, bleach, detergent, and even caustic drain cleaners (see How Can I Get Rid of Drain Flies?).
One possible sign of an undetected mold problem in your home or office could be the presence of Phorid flies, sewer flies or some other gnats or bugs.
For effective drain fly treatment, use three products: Forid Drain Gel Cleaner, Gentrol IGR Aerosol, and Pyrid. Forid is an organic microbial grease degrader that breaks down organic material and waste, which will eliminate their food sources and their breeding grounds.
They do not bite, sting, or spread diseases, but their decaying bodies may cause allergic reactions. They can also spread bacteria from trash, decaying vegetables and fruits. Drain flies breed in areas that are moist and have a lot of organic remains, including: Sinks.
They will breed in any moist area that they can find. So if you are facing a drain fly infestation that you can not get a handle on, you may want to look deeper for the cause of these insects. It could be stemming from a leaking pipe or drain under the sink or even a leaking pipe inside of your walls.
Do Drain Flies Die in Winter. Most fly species cannot survive outside temperatures below 32°F (0°C). They die unless they find a warm and conducive place to overwinter, such as your home. Drain flies are one of the few insects that can tolerate cold weather conditions.
Drain flies can breed outdoors during the summer with adults entering homes through open doors or windows. Low, wet areas where air conditioning units drain, or clogged guttering are excellent places for these insects to develop.
The drain flies are not coming up from the P-trap. They are traveling inside from outdoors and reproducing in the organic matter that builds up on the walls inside the drain. You should use 4oz of DF5000 drain fly gel in each drain in the infested room every night for a week.
Essential oils are sometimes used to keep flies away from infested sections and also to kill them. Lavender, eucalyptus, peppermint, lemongrass, and citronella are just a few of the scents that insects despise (with lavender probably being the most effective).
Drain flies don't cause any damage to your home or plants, but here's what you need to know about these pests and your health. Do drain flies bite? Drain flies don't bite or sting people or animals. However, if they die in your home, their decaying bodies can cause allergic reactions in some people.
Because drain flies come out at night, do this experiment before bed. Wipe any standing water in the drain. Use one strip of tape. Tape the drain with the sticky side down.
Preventative Maintenance
Pouring bleach into the drain when the unit is not operating can leave residual bleach, which will damage the drain pan and line. Using vinegar for preventative maintenance throughout the year will keep your drain clean and clear and will not damage your line.
Many people associate the control of drain flies and bleach. The idea that pouring bleach down the drain gets rid of drain flies is actually a common misconception since doing so rarely helps get rid of these insects.
Drain flies, also known as sewer flies, filter flies, moth flies or sink flies, look similar to the average house fly as they are very small – about an eighth of an inch – and black/brown. They also have a unique vein pattern in their wings, which are covered in tiny hairs. They leave a powdery smudge when crushed.
The vinegar's smell will attract the drain flies, and the wrap will trap them inside the bowl. Another option is to mix a few drops of dish soap with a cup of vinegar. The vinegar attracts the flies, and the dish soap makes it impossible for them to stand on the surface, so they drown.
Some species hold the wings out to the side, which gives them a moth-like appearance—hence the name "moth fly." They are weak fliers and make irregular, hesitating flights covering only a few feet in short, jerky lines. Eggs are tiny, brown or cream-colored and are laid in irregular masses of 10 to 200.