# Can I make a self-contained mini-ecosystem?
**URL:** https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364
**Category:** Factual Questions
**Created:** [August 9, 2005, 11:49pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364 "2005-08-09T23:49:06Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@FlippyFly](https://boards.straightdope.com/u/FlippyFly)
#### Post date: [August 9, 2005, 11:49pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/1 "2005-08-09T23:49:06Z")
Here’s my vision… a sealed container, larger than a basketball but smaller than a dishwasher. Inside, I want a complete ecosystem. I want water, air, plants, and preferably a small animal, like a fish, lizard, or even just insects. I want the system to live indefinitely on its own with no interference. That means no feeding, no cleaning, no adding or removing anything. I want to stick it in the sun, watch the plants grow and die, watch my animal eat, sleep, move, poop, have babies, live and die. I want water to evaporate, condense, be drank and peed. I want O2 to become CO2 and then back to O2 again.
Can it be done? What plants, animals, minerals, or other things would be best?
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### Author:  [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)
#### Post date: [August 9, 2005, 11:50pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/2 "2005-08-09T23:50:55Z")
Like [one of these?](http://www.virtualpet.com/vp/farm/ecos/ecos.htm)
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### Author:  [@Finagle](https://boards.straightdope.com/u/Finagle)
#### Post date: [August 9, 2005, 11:54pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/3 "2005-08-09T23:54:06Z")
Sure. [You can even buy them commercially.](http://www.eco-sphere.com/index.html)[But’s it’s likely a bit tricky to get everything right.](http://depts.alverno.edu/nsmt/archive/luebke.htm)
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### Author:  [@Thin\_Lizzy](https://boards.straightdope.com/u/Thin_Lizzy)
#### Post date: [August 10, 2005, 12:06am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/4 "2005-08-10T00:06:27Z")
How about a terrarium? not the same but still pretty cool
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### Author:  [@FlippyFly](https://boards.straightdope.com/u/FlippyFly)
#### Post date: [August 10, 2005, 1:03am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/5 "2005-08-10T01:03:35Z")
“Because the EcoSphere is a living thing we know it will die some day.” - that’s no good, a true and balanced system wouldn’t die. Cool anyways. I might have to get one.
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### Author:  [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)
#### Post date: [August 10, 2005, 1:12am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/6 "2005-08-10T01:12:32Z")
> [@FlippyFly](#):
>
> “Because the EcoSphere is a living thing we know it will die some day.” - that’s no good, a true and balanced system wouldn’t die. Cool anyways. I might have to get one.
Have a whack at it. It is a very difficult problem and I am sure that many scientists would love to see a long-term, workable, design.
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### Author:  [@kanicbird](https://boards.straightdope.com/u/kanicbird)
#### Post date: [August 10, 2005, 1:57am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/7 "2005-08-10T01:57:45Z")
Why they are you adding sunlight, which means you are adding matter (E=mc^2)?
Have some ballz, seal that sucker in a dark room and add some plutonium
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### Author:  [@PBear42](https://boards.straightdope.com/u/PBear42)
#### Post date: [August 10, 2005, 2:14am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/8 "2005-08-10T02:14:53Z")
Difficult problem indeed. The most famous, attempt was [Biosphere 2](http://www.biospheres.com/experimentchrono1.html). It failed.
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### Author:  [@Padeye](https://boards.straightdope.com/u/Padeye)
#### Post date: [August 10, 2005, 3:35am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/9 "2005-08-10T03:35:08Z")
IMHO Biosphere 2 was a successful failure, and in more ways a missed opportunity. I worked there for nearly seven years so I may be a little biased but I’ll see if I can shed some light on the OP.
One of the most serious problems with Biosphere 2 or pretty much any sealed ecosystem is that the ratio of living stuff to atmosphere is dramatically higher than on biosphere 1 (the earth). The consequence is that any cyclical changes to the atmosphere are so dramatic that they can threaten the survival of the life inside before they settle into equilibirium. In Bio2 the two biggest problems were excess CO[sub]2[/sub] caused in part by unusually high levels of cloud cover in Arizona during the first two years and oxygen depletion from soil microbes. I don’t know if either of those would have reached equilibirum but just before oxygen was injected the atmosphere was so depleted that some of the crew said a candle would not burn. The crew who were all fit, trim people reported being exhausted after the effort of climbing one flight of stairs.
**kanicbird** the stated goal of Biosphere 2 was to make a materially sealed ecosystem with only energy and information being exchanged. In that light we weren’t too worried about relativistic mass.
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### Author:  [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)
#### Post date: [August 10, 2005, 3:35am UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/10 "2005-08-10T03:35:28Z")
> [@PBear42](#):
>
> Difficult problem indeed. The most famous, attempt was [Biosphere 2](http://www.biospheres.com/experimentchrono1.html). It failed.
Nay, if your going to disregard the size restriction, the most famous attempt would be “Earth.” Which hasn’t failed yet, but the warranty’s up in a few billion years. By then, perhaps the experiment will be “our universe,” which buys us (or whoever) many billion more.
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### Author:  [@wevets](https://boards.straightdope.com/u/wevets)
#### Post date: [August 10, 2005, 4:06pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/11 "2005-08-10T16:06:05Z")
> [@FlippyFly](#):
>
> “Because the EcoSphere is a living thing we know it will die some day.” - that’s no good, a true and balanced system wouldn’t die. Cool anyways. I might have to get one.
Everything dies eventually. Many of these eco-spheres or [bottle biologies](http://www.bottlebiology.org/) last for years and years. Hard to expect anything better.
How long do you want it to last?
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### Author:  [@scr4](https://boards.straightdope.com/u/scr4)
#### Post date: [August 10, 2005, 6:12pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/12 "2005-08-10T18:12:27Z")
> [@wevets](#):
>
> Everything dies eventually. Many of these eco-spheres or [bottle biologies](http://www.bottlebiology.org/) last for years and years. … How long do you want it to last?
IIRC, the “EcoSphere” isn’t large enough (or equipped properly) to allow the shrimp to reproduce. Even under ideal conditions, its “life span” is limited by that of the shrimp you put in.
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### Author:  [@kniz](https://boards.straightdope.com/u/kniz)
#### Post date: [August 10, 2005, 6:38pm UTC](https://boards.straightdope.com/t/can-i-make-a-self-contained-mini-ecosystem/316364/13 "2005-08-10T18:38:46Z")
> [@scr4](#):
>
> IIRC, the “EcoSphere” isn’t large enough (or equipped properly) to allow the shrimp to reproduce. Even under ideal conditions, its “life span” is limited by that of the shrimp you put in.
I believe you are correct, because of this statement
> [@](#):
>
> **The life expectancy of the shrimp is known to exceed five years, and in many spheres, shrimp are still thriving after 7 years.**
but then why did they say this?
> [@](#):
>
> **The shrimp and snails (the animals) are the only animals known to live in these tiny worlds. They are masters of utilizing their resources, without overpopulating, or contaminating their environment.**
😕 [sup] **overpopulating? Why not “they don’t multiply”?** [/sup]
**Padeye** I was very interested in you comments. I always wondered why that experiment didn’t work.