Catch 50 Fleas in One Night





Introduction: Catch 50 Fleas in One Night

With this home built flea catcher I was able to catch 50 fleas in one night. Yes I certainly did count them!

I have seen several other prototypes on the internet, but I wanted to share my experience with my results.

The part list.
Dish Soap
Ground Black Pepper
LED Night Light
Container Lid
Toaster Over Tray

There are several flea traps on the market. Here is one such example. However they contain a sticky pad that you will need to eventually replace. I am adding this language expressly for the "I Could Make That" Contest. Please vote and share with a friend =)

Step 1:

This part of the experiment verifies that soapy water will work for the trap, but regular water will not. The soap reduces the water surface tension. Basically this trap wants to drown the flea, not let it glide on the surface of the water. Why did I use pepper? It is similar in size and weight of a flea. If the solution is correct and it pulls a small grain of pepper, then it will definitely pull down a flea into the trap.

Step 2:

Now that we know how to verify the solution. We take our lid, fill it with water, and squeeze generous amounts of soap into it. The ratio is unclear at this time, but with the pepper it doesn't matter. Simply stir the water a bit and keep adding soap until the when you add a pinch of pepper, it sink right to the bottom of the lid. The tray is here so that my cat doesn't drink the soapy water. I doubt it would happen because soapy water doesn't taste good, but it is here as a precaution.

My best guess on the water to soap ratio: 2 cups water to 4 TBSP soap.

Step 3:

Okay here you will see the trap all setup and in place. The LED night light is plugged in right above it. The fleas will jump towards the light, and bam they will sink into the soapy water.

Step 4:

Here are the results. I counted 50 fleas caught in trap in the morning. So I will count this as success.

On the left side of the picture is some of the pepper scattered about, but the rest are in fact fleas.

Step 5:

As a side note I must say I did see the very first flea land into the water, before I added to soap. The flea just glided onto the water, but once I added the soap the little guy couldn't glide on the water surface tension and sank to the bottom. I must admit that I did feel bad for the little guy. He did thrash around a bit just like any other creature of the animal kingdom might do if they were drowning. This is a warning that this method is non toxic and eco friendly, but it will indeed drown any flea that lands in the trap.

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Tried this out last night after it got dark for a few hours. Worked pretty good I'd say. I'll keep doing this for a few more nights but I have a question. I have no carpets in my house it's all hard wood floors is there anything else I can do/use that's safe because I have small children and we're all getting ate up. Any suggestions would be appreciated!!


If you no carpets even better. Fleas tend to lay the eggs in the carpet which can be gross. I would recommend vacuuming and mopping the floors more often. Soapy water with the optional splash of bleach would also keep the floors clean and sanitised.

Great work. I love seeing the photo. I would do this for a few nights and put fresh water until you stop catching fleas.

Thanks. I've done this before & knew to use soapy water. (use soapy water to rinse off a flea comb if you animal is bad enough you need to comb them out.) But you had some useful ideas. And verified that an LED bulb will work, which is the info I was searching for. Please, everyone, don't use sticky traps. I caught a gecko in mine which I didn't want. Especially never use those glue traps for rodents. They can catch a lot of things you wouldn't have wanted to harm. I volunteer at a wildlife center and we often have to deal with birds stuck in the traps.

Great to hear this project is helping the wildlife. The whole point of the project was the keep fleas under control without negative effects to the environment. Great to hear that this works better than sticky traps.

Fleas are attracted to yellow light, carbon dioxide, movement, heat and vibration. Use a tea light in the plate bowl/pan off soapy water. They have five testing of all different wavelengths of light and found that 80% of the fleas in a dark room will head for the light source within 40 min... pasted below... But candle or tea lights work the bomb!

I highly disagree with this comment. Most insects cannot see yellow light. Also the research and the whole point of the project was to prove that fleas do not go after heat. Hence a LED light uses less power and is much safer than using a candle.

One part of the project was to make a cheap flea trap. This trap only uses a few drops of soap. Using lots of dish soap would create a similar affect, but soap costs more than using water.

Again you do not need a heat source, but you do need a light source. But if you are catching fleas everywhere you may need to thoroughly clean your room. The traps you are using are working from the fleas randomly jumping inside VS using a beacon to get all of them out of your room.

Hey! This sounds great and has already helped a little (caught some of them).

I have one question though - can I use the same water multiple times? I mean should I make a new soapy water for every night or can I use the water from last night if there are not too many fleas inside?

Thank You!

I'm sure you can you use the same water for the week. Eventually the water might get dirty, it might evaporate, or the fleas in the water might be gross. Use your best judgement. I have found after the first night most of the fleas for that room have been trapped. But you could keep it going for a few nights to see what happens.