How to Keep Flies Away Using Bag of Water with Pennies

Are you fed up with chasing flies away at your outdoor parties? A new way to make flies stay away is with a bag of water and some pennies. This method is growing in popularity in the US, showing success at places like restaurants and homes. People are wondering if it's real or just a story.

Understanding the Science Behind the Bag of Water Trick

The bag of water with pennies trick fights flies using science. Flies see many images due to their eye structure. Light bouncing off the water and pennies confuses them. This makes them fly away from the bag.

The trick works by using a simple but clever idea. Since flies see it as dangerous, they avoid it. The bag acts like a rainbow, but for the flies, it's annoying more than pretty.

A study from North Carolina State University says water bags might attract flies. But, this study didn't look at bags with pennies. We think the added pennies could make this trick not work for the flies.

Many people are interested in why the bag of water trick might or might not work. A video about it has been watched over 159,800 times. This shows how curious people are about natural ways of keeping flies away.

Compound Eyes
Light Refraction
Insect Behavior
Flies have compound eyes, composed of thousands of individual lenses that are highly sensitive to changes in light.
The light refracts through the water-filled bag and reflects off the pennies, creating a confusing visual effect.
The visual disruption caused by the bag of water with pennies is perceived as a threat or an unsuitable landing spot by flies, prompting them to avoid the area.

The bag of water trick shows how smart nature is. It teaches us about how insects see the world. By using what we know, we can make places that flies don't like. This keeps them away from where we don't want them.

The Pennies in the Bag of Water Fly Repellent Technique

Adding pennies (or other shiny things) to a water-filled bag goes beyond just the light trick. It's thought to make the trick better at keeping flies away. The pennies in the water look like the eyes of a big bug to flies. This might scare them away because they think there's a threat there.

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This method uses light and shininess to stop flies from coming. Many studies have looked into if it works:

  • The control fly strip collected 95 flies over 48 hours, with an average of approximately 0.38 flies per square centimeter of exposed fly paper.
  • The fly strip near the bag of water accumulated 54 flies in a smaller exposed area, resulting in about 0.44 flies per square centimeter, higher than the control group.
  • The fly strip positioned at 0.6m away from the bag had 112 flies, or 0.46 flies/cm2.
  • The fly strip at 1.2m captured 149 flies or 0.61 flies/cm2.
  • The fly strip at 1.8m away trapped 130 flies, averaging 0.53 flies/cm2.

Even with these tests, the data shows a weak link. There was almost no connection between how far the flies were and how many of them were caught by the pennies method. Sometimes the bag of water even drew flies in.

Many in the South of the U.S. still believe this trick works. But experts warn not to rely too heavily on it. Using pennies in water to stop flies might not work as well as people hope. There isn't enough proof it really does cut down on the bugs.

How to Keep Flies Away Using Bag of Water with Pennies

Flies can really bug us, especially when it's warm. But, there's a neat and cheap trick that many in the U.S. are using. It's called the "bag of water with pennies" method. This trick comes from Mexico, where restaurants have used it. Now, people in Tennessee are loving it for keeping flies off.

Want to try this trick out? Here's how:

  1. You need a clear, sealable plastic bag and some pennies (4-6 of them).
  2. Put clean water in the bag, enough to cover the pennies.
  3. Seal the back tightly, removing all air inside.
  4. Hang the bag with water and pennies where you don't want flies, like near doors or patios.

How does it work? Some think the pennies look like big insects' eyes in the water. This scares flies off, or so the idea goes. It's even believed that older, darker pennies might chase flies more effectively.

Many have had success with this trick. It's said to cut down on flies by almost 90%. This includes places like restaurants, backyards, and classrooms. What's great is it's a natural, eco-friendly way to push flies away. Plus, it's simple and costs next to nothing.

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Alternative Methods for Repelling Flies Outdoors

The bag of water with pennies is a known way to keep flies at bay. Yet, there are more tricks to try. Old CDs can be hung outside with their shiny sides outward. Also, fans designed to drive flies away run off batteries. And there's the trick of hanging plastic bags full of water near where you eat.

The Tennessee Farm Bureau notes the bag of water with pennies confuses flies with how it refracts light. This means using pennies in glasses of water can cut down on flies almost entirely. Placing several of these glasses near the food area greatly reduces the number of flies.

Oddly enough, older and maybe even dirty pennies work better for this method. Furthermore, bags filled with water are common sights in places wanting to deter flies like Mexican restaurants and schools in Tennessee.

However, these natural ways might not always work for everyone or every situation. It seems some folks have found the penny-water bag method ineffective, especially in places like barns. So, results can vary.

For a more guaranteed and extensive solution, professional help is available. Insect control experts offer more reliable ways to deal with flies outdoors. By looking into different approaches, you can pick what works best for your home or business. This way, you can enjoy the outdoors without unwanted pests.

Success Stories and Testimonials

The bag of water with pennies trick to keep flies away is a hit! Users from all over have shared how flies vanished from their outdoor spots. Areas like their gardens or where they eat saw fewer flies.

In a Facebook group about cleaning tips, many found this method super effective against flies. A lady said she didn't see any flies for three weeks after starting. She was amazed. Others in the group agreed, saying it helped them too.

In Australia, a clever mom shared another trick. She used a lemon with cloves stuck in it to repel flies. It started working in just 30 minutes. Someone else in a cleaning group noted it kept flies off her dogs by using the same lemon trick outdoors.

People have really loved the bag of water and pennies. They've seen a big drop in fly numbers outdoors. This simple idea continues to gather great reviews for its low cost and eco-friendly benefits.

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Debunking Myths and Misconceptions

Many people have tried the bag of water with pennies to scare off flies. It's true, this method has become quite popular. But, there are others who doubt its effectiveness. They point to experiments that say it doesn't work that well.

Let's take a look at the facts and see if this trick really works:

  • A penny falls at a speed of 44km/h (27mph). It's too slow to scare flies away visually.
  • Even though bees are light, they can fly because of their strong wings. This fact shows that the bag of water's refraction doesn't work as an illusion to scare flies off.
  • Houseflies can actually live for many weeks, not just one day. This shows the flaw in thinking the bag of water can get rid of flies over a long period.

The bag of water with pennies might keep flies away for a bit. But, scientific studies suggest it might not work well in the long run. It could be better to look for other methods that are based on real evidence.

Scientific Evidence
The bag of water with pennies creates a visual disturbance that scares flies away.
The terminal velocity of a penny is unlikely to create a significant visual disturbance.
The refraction of light in the bag of water mimics a predator, deterring flies.
Bees can fly despite their small wings, debunking the idea that the refraction alone scares flies.
Houseflies only live for a day, so the bag of water method can effectively eliminate them.
Houseflies can actually live for several weeks, making the long-term effectiveness of the technique questionable.


The bag of water with pennies might not be a perfect fly repellent just yet. People have noticed it working outside, but scientists aren't sure it's reliable. They are still looking into how well it works.

This method uses light and reflections to confuse flies. While it sounds like it could work, the results can be very different. For the best way to deal with flies, keeping things clean and using trusted fly control methods is key.

In the end, this DIY trick could help a bit, but experts and their advice are the way to go. Whether at home or in a business, the best solution for flies comes from following what science knows works best.

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