Introduction: Ecosystem in a Bottle

Im Sadie Kariko, and the project I chose to do was the soda bottle ecosystem. My goal is to have the ecosystem thrive all together. I got to choose between a closed and open ecosystem. The closed ecosystem has to work all together, while an open ecosystem can use some of the outside materials like different gasses.


- 2 plastic water bottles

-potting soil


-fish gravel

-one plant

-water plant (s)

-three fish

-two snails

Step 1: Components of the Ecosystem

I have created the top part of the ecosystem, which is we're the plant goes. The plant gives off oxygen for the fish.The middle part is were the gas exchange happens, that helps both the fish and the plants live. The bottom part of the ecosystem is where the fish and the water plants are kept and give off C02, which the plants eat. They are all important to the ecosystem because they all work together to maintain the ecosystem. Without one of them, they all wouldn't work.

Step 2: Cut the Bottles Up

The first step I took was to cut up the bottles. I took one bottle, and cut the top off. Then I Took the top and put it to the side for later. Next I took the second bottle and It cut it into three pieces. I took the middle, and the bottom and put them to the side.

Step 3: Setting Up the Bottle (bottom)

Get the bottom of the first bottle. Take two cups of fish gravel and pour it into the bottle.

Step 4: Add Your Water Plants

Move some of the gravel out of the way. Wash the roots of the water plants, and place them in the gravel. Make sure the roots are covered.

Step 5: Add Water, Fish, and Snails

You last step for the bottom is to add your fish and snails. If you have fish food, or algae wafers. Put that in with them so they feel "at home."

Step 6: Setting Up the Top

Take the cap of the bottle and drill five holes in it. This is so there can be gas exchange between the plant and the water. Flip the bottle top upside down. Put little potting soil in the top, and then add your plant.

Step 7: Putting It All Together

Take the bottom from the first bottle. Place the middle on-top of it, followed by the top of the second bottle. For the next three or so weeks, take notes on to keep track on how your ecosystem is doing.

Step 8: Week One

-Day one.

The first day all of the fish and snails have died. I think this is because the snails did not like the living habitat, and when the died they released toxins in the water. Or both organisms weren't getting enough oxygen.

-Day 3

I put small holes in the middle section of the ecosystem. I also got new fish, but I didn't get any new snails. The fish are happy, and the ecosystem is thriving.

Step 9: Week Two

-Day 9

All the fish are still alive, but the plant has died. I think it is because I over watered it. I got a new plant, and re-planted it. I plan on keeping the plant off for several days to make sure the fish stay alive.

-Day 12

I put the plant back on and the ecosystem is still thriving. The fish are still alive. The fish eat more and more each day.

Step 10: Final and Third Week

-Day 15

The plants are doing very well, but it seems to be dropping a little. I decided to move the ecosystem into a sunnier spot in my house. I also have had to add a little bit of water every four days.

-Day 21

All of the ecosystem is working, there is no additional notes.

Step 11: Conclusion

I do think this was a success. Through all of the struggles and bad parts of making this, I do think this is a success because the fish and plants are thriving together. If I was to do this again, I would change the design of the bottle experiment to something more simpler. I would not use snails. Lastly, I think it will last another month before I have to move it into a bigger space.

First Time Author Contest

Participated in the
First Time Author Contest