How to Make a Jellyfish in a Bottle




Introduction: How to Make a Jellyfish in a Bottle

About: In a valiant attempt to keep myself from dying of boredom, I create.
When I showed this to my 3 year old grandson, his comment was “Wow!” and when it was time to go home; he wanted to take it home with him.  Yes, it’s that much fun, as well as easy and cheap because you use stuff from your recycle bin to create it.  So here is how to make a Jellyfish in a Bottle.

Step 1:

Empty water bottle or 2 liter bottle
Translucent grocery (t-shirt) bag
Food coloring
Label adhesive remover

Step 2:

Make sure your water bottle/2 liter bottle is clean and label free.  Some Goo Gone or WD40 will take off the adhesive. Fill the bottle with water and put a drop or 2 of food coloring in the water.

Step 3:

Shake the bottle for an even distribution of the color.  Set aside as you make the Jellyfish.

Step 4:

Take the almost transparent t-shirt bag and fold it flat. .

Step 5:

Cut off the handles and the bottom of the bag.  Cut off the area of advertising. 

Step 6:

That will leave you enough bag left to cut in half and you could create 2 Jellyfish.  You only need one per bottle

Step 7:

Take the center of the piece of t-shirt bag and make a bubble, it will be a bubble once you wrap some of the thread loosely around the area (don’t make it tight, you want to be able to add water and air to the bubble), tie the thread off. 

Step 8:

Turn it over; you should be able to see the hole leading to the center of the bubble.  In case you haven’t figured it out, this is the head of the Jellyfish.

Step 9:

Next cut the parts of the t-shirt bag, hanging down from the head. So that you will have trailing tentacles, you will be cutting more away than what you will leave behind.  Don’t have more than 18 tentacles of various lengths. 

Step 10:

If you leave too many, the jellyfish will not be able to swim through the water in the bottle. It will be just a big blob of tentacles, (been there done that).

Step 11:

Turn the Jelly fish over and find the opening to the head.  Blow into the opening to fill it with air.  Add enough water so that the head is half filled with air and half filled with water. 

Step 12:

Twist the head tight.  Stuff it and the tentacles into the water bottle and screw on the cap tight. 

Step 13:

Turn it up and down and watch the jellyfish swim from the bottom to the top.  Enjoy!

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    Question 10 months ago

    When you say twist the neck of the jellyfish, do you mean tighten string?


    5 years ago

    Jan. 2017, trying this for my daughter. We have regular 2L pop bottles and are having an awful time getting the "head" to fit past the small opening once the air is added. Are you using a wider mouthed bottle?


    Reply 5 years ago

    I did use a regular size 2 liter bottle. Use what ever you want to make this work for you. It really won't make any difference. Thanks for asking and commenting.


    10 years ago on Introduction

    Very nice. but if there was a longer transparrent pole you could hook up an arduino and motor then it will automaticly twist

    Well Done


    Reply 10 years ago on Introduction

    You know I still don't under stand what an arduino is and how it works. That would be cool. Maybe you need to upgrade this instructable with an arduino and motor. I would be blown away. Thanks for looking.


    Reply 10 years ago on Introduction

    I live in South A so I don't even GET ardunio but if I had the time I could make a schematic that doesn't involve ardunio. It would use tilt sensors to reverse the current going to the motor then once its turned reverse it again.

    Pretty simple I will put  up some drawings soon. MAke it then give you credit for my idea :-> :->  or :) :)