Will Bleach Kill Drain Flies (Or Your Pipes)?

Last Updated On June 12, 2024

Updated on June 4, 2022



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Will Bleach Kill Drain Flies (Or Your Pipes)

Swatting at drain flies won’t resolve the problem when the flies live and grow inside your pipes. So maybe you’re looking for a nuclear option. Are you considering bleach to kill the pesky drain flies coming from a drain in your home?

The strength and cleaning power of chlorine bleach may seem like a reasonable solution, but what does that mean for your drain pipes? Let’s get into it.

In this PlumbingNav guide, we cover:

  • Will bleach kill drain flies?
  • What are drain flies?
  • How to prevent drain flies
  • How to get rid of drain flies

What's In This Guide?

      Will Bleach Kill Drain Flies?

      No. Bleach will not resolve a drain fly infestation.

      Bleach may kill the drain flies it comes in contact with. However, it will not destroy the protective layer around drain fly eggs, meaning the drain flies will hatch and return as soon as they mature. 

      The newly matured flies will lay more eggs, and it will become an endless cycle of killing the new generation of drain flies. 

      However, using that much bleach will likely damage your plumbing. 

      Instead of bleach, watch the video below to try the following 5 methods to get rid of drain flies:

      1. Boiling water (mildly effective)
      2. Vinegar and baking soda (mildly effective)
      3. Fly trap (moderately effective)
      4. Fly Killer (moderately effective)
      5. Drain cleaning (highly effective)

      How Bleach Affects Your Plumbing Pipes

      Bleach consists of 3% – 8 % sodium hypochlorite (NaOCl). This chemical disinfects especially well and works well to clean mold and mildew. However, the chemical also has the ability to eat at your pipes, especially when used in high concentrations. Especially if you pour bleach down the drain without diluting it.

      If you unknowingly use bleach to clear a clog or eliminate drain flies, you won’t get positive results. You may, however, unknowingly create a drain leak.

      Never ever mix bleach with other chemicals, such as chemical drain cleaners or products that contain ammonia. The chemical reaction creates a toxic reaction that you or other people in your home may accidentally ingest. 

      What are Drain Flies?

      Drain flies, or sewer flies, refer to small flies often found in pipes. Most of the time, you will find them coming from your kitchen sink drain, bathroom sink drain, or shower drain

      You will notice more activity at night and that the flies don’t actually fly well and only fly small distances at a time.

      Drain flies do not bite, and they do not spread any disease. They don’t present a health hazard, so you don’t need to treat this as an emergency situation. They also don’t cause significant damage to your pipes. However, they indicate dirty pipes and create an unsettling nuisance. 

      Identifying Drain Flies

      Drain flies don’t grow larger than ⅕” in length and have small hairs covering their body and wings, making them look like tiny moths. 

      Some people mistake a drain fly for a fruit fly. However, fruit flies are much larger and don’t tend to take shelter in drains. Same for standard house flies.

      Drain Fly Reproduction

      Drain fly eggs hatch in 32 – 48 hours when under ideal conditions (moist environment around 70 degrees). After eggs hatch, the drain fly larvae feed off of the organic matter in your drains, such as oil, grease, and food waste, for up to 14 days before maturing into adult drain flies. 

      Once adults, drain flies mate and lay eggs in irregular amounts between 10 – 200 eggs at a time. 

      Sink flies have a life expectancy of roughly 2 weeks.

      did you know will bleach kill drain flies

      How to Prevent Drain Flies: Skip the Bleach

      The best way to prevent drain flies is to stop your drains from being so appealing to them. Organic material in your pipes and standing water in your pipes as a result of a clog create the ideal environment. Don’t pour cooking oil down the drain, and consider pouring salt in at night.

      Keep up with your regular plumbing maintenance by performing regular drain cleaning with enzymatic drain cleaners that are safe for your pipes (or the standard mixture of boiling water, white vinegar, and baking soda). This will also curb smelly sink drains.

      Getting rid of clogs with regular drain and sewer line cleaning means you eliminate the organic material the flies rely on for nutrients. 

      You can also avoid clogs by using drain strainers and being mindful of what you can and cannot dispose of down your drain.

      How to Get Rid of Drain Flies Without Bleach

      Once drain flies become a problem, you’ll need to take more drastic measures in the form of pest control products safe for your PVC pipes

      You can’t use chemical drain cleaners or typical pesticides as they won’t kill the larvae. 

      Instead, try DF-5000 Drain Fly Eliminator (recommended by Michigan State University) or a similar product specifically designed for flies. DF-5000 Drain Fly Eliminator is a “highly selective active bacteria complex” and not chemical-based. 

      Buy DF-5000 Drain Fly Eliminator on Amazon!

      Alternatively, you can use a drain brush (not a snake) with tassels that can remove the eggs and larvae in your drains at the source. The brush’s main limitation is that it only reaches so far into your drain. 

      Finally, you can attract the drain flies outside of the drain to make the experience easier. Drain flies enjoy sweet flavors, so put out a bowl of vinegar but add some sweet temptation with a couple of pumps of dish soap. 

      You still have to address the issue in your drain, but you’ll have fewer flies buzzing around as you work. 

      You can find a drain trap online that uses similar principles as your homemade trap but is designed to work inside your drain. 

      Frequently Asked Questions on Using Bleach to Kill Drain Flies

      Will bleach kill drain flies?

      Bleach should not be used for drain cleaning or drain fly removal. Instead, use bleach for cleaning mold and mildew in your pipes. When you do need to use bleach in your drain, use the substance sparingly, dilute with plenty of warm water, and flush the drains thoroughly afterward. 

      Are drain flies dangerous?

      Drain flies, while a nuisance, do not bite. Nor do they spread disease. Drain flies do not present a health hazard to humans. Nonetheless, you still want to get rid of them as quickly as you can. 

      What instantly kills drain flies?

      Since bleach won’t kill the eggs or larvae, you’ll need another solution. Many experts suggest using DF-5000 Drain Fly Eliminator, but there are a number of products on the market specifically designed for drain flies.

      While it may be tempting to get multiple uses out of your drain cleaner, and while it may help temporarily, drain cleaner and bleach won’t get the job done properly.

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      About Plumbing Navigator

      We write about "all things plumbing," helping you navigate common questions, repairs, and the best plumbing products on the market.

      About Plumbing Navigator

      We write about “all things plumbing,” helping you navigate common questions, repairs, and the best plumbing products on the market.

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