Ecosystem in a bag of holding

[Studoku]

This idea was formed from a discussion in my D&D group, about keeping a halfling in a bag of holding for longer than the 10 minutes of air would allow. This lead to keeping plants in the bag to provide oxygen, which lead to animals to provide CO2 for the plants. I thought the idea of carrying a small ecosytem in a bag was pretty cool, especially if that ecosystem was large enough to support carnivores.

I'd like to use this idea for my next character and I'm looking for suggestions as to how to accomplish this.

[Fax Celestis]

Cast genesis into the bag of holding?

[Ravens_cry]

Cast genesis into the bag of holding?

This spell cannot create life (including vegetation)

A Bag of Holding already IS a demiplane, so all genesis would do would be to possibly enlarge it. Also, you will need a source of energy for the plants. The daylight spell might do so, though since it doesn't affect Vampires and creatures with similar weaknesses, it is debatable. Still, if I was DM, I would allow it.
I think there is an item that provides fresh air though, so just sticking one of those in their would probably be easier.

[Fax Celestis]

A Bag of Holding already IS a demiplane, so all genesis would do would be to possibly enlarge it. Also, you will need a source of energy for the plants. The daylight spell might do so, though since it doesn't affect Vampires and creatures with similar weaknesses, it is debatable. Still, if I was DM, I would allow it.
I think there is an item that provides fresh air though, so just sticking one of those in their would probably be easier.

Ooh. Bottle of air and a permanencied daylight spell. Maybe some sort of contingent darkness too, to suppress the daylight every 12 hours for12 hours to provide night and day.

[Studoku]

A Bag of Holding already IS a demiplane, so all genesis would do would be to possibly enlarge it. Also, you will need a source of energy for the plants. The daylight spell might do so, though since it doesn't affect Vampires and creatures with similar weaknesses, it is debatable. Still, if I was DM, I would allow it.

Since plants in the real world can be grown using artificial light, it should work.

[Ravens_cry]

Ooh. Bottle of air and a permanencied daylight spell. Maybe some sort of contingent darkness too, to suppress the daylight every 12 hours for12 hours to provide night and day.

Hehe, it's good to kill cat girls.
Or does biology kill something different?

[Copacetic]

Even better: Make them Vampire plants. No need for sunlight, and they can feed off the Animals.

[Collin152]

Hehe, it's good to kill cat girls.
Or does biology kill something different?

Since physics kills catgirls, which are bilogical, it only makes sense for biology to kill black holes.

[Ravens_cry]

Even better: Make them Vampire plants. No need for sunlight, and they can feed off the Animals.

Yeah, but what do the animals eat? The plants? That is a thermodynamically untenable situation. Besides, the whole reason for the bag o' holding terrarium, is to hold the people inside indefinitely. You don't want your oxygen supply feeding on your passengers, do you?

[Funkyodor]

Or just give the halfling an necklace of adaptation so hes always got fresh air to breathe.

[elliott20]

funkyodor, they COULD do that, but that would be too easy and far less fun!

[Sstoopidtallkid]

First, you need to go with a Portable Hole. The largest BoH is only ~7x7x5. Not big enough for a real ecosystem. I'd see if you can increase the cost to increase the size. 900 cubic feet is nice, but really, an ecosystem requires more if you don't want to be re-introducing plants every few days.

[Cybren]

it's taken THIS LONG for a Bag Wars post?

[elliott20]

how about if you just grow some fungus in there something? technically it would be an ecosystem.

[Ravens_cry]

how about if you just grow some fungus in there something? technically it would be an ecosystem.

Fungus don't make oxygen, and need a something dead to break down. Seriously, they are more like land based sponges then plants. I read in Discover magazine that on the GENETIC level, fungus are more like animals then plants. They would be important in any ecosystem, but they can't do the whole job. When I said terrarium, I was half joking, but actually, that is what this is, a terrarium with its own light source, and they can be quite small. Google them up for some ideas on designing this place.

[Bayar]

This reminds me of the "There is a town in one of my PC's tummy" thread. That was WIN.

You could always stick the corpses of your victims enemies in there and put some fungus to degrade it...

It would actually be a really good deathtrap for gnomes !

"Hey look ! I got a whole ecosystem in my BoH ! Wanna check it out ? *bluff check optional*

Gnome: Sure !

5 minutes later: Cant breathe, air filled with spores..."

[Fishy]

It's actually been done, minus the bag of holding. Still needs a light source, though, and I don't think they live forever.

[Harp]

This might be more feasible if the character could create or discover an existing pocket plane. I vaguely recall something about gray circle druids from a FR campaign I played in, but it might have been non-canon. I'm not familiar enough with the setting to know, but I think pocket planes are universal in most campaigns anyhow.

Alternatively, Flesh to Stone and Stone to Flesh are win for hiding people in bags of holding and portable holes indefinately, assuming you've got a wizard or someone who can use the scrolls.

[Tsotha-lanti]

This idea was formed from a discussion in my D&D group, about keeping a halfling in a bag of holding for longer than the 10 minutes of air would allow. This lead to keeping plants in the bag to provide oxygen, which lead to animals to provide CO2 for the plants. I thought the idea of carrying a small ecosytem in a bag was pretty cool, especially if that ecosystem was large enough to support carnivores.

I'd like to use this idea for my next character and I'm looking for suggestions as to how to accomplish this.

Plants produce a net of approximately +/-0 carbon dioxide, because they release carbon dioxide during the night and when they rot. Even while active, I really doubt the filtration is anywhere near 100% oxygen returned. (Edit: And I really doubt people exhale as much oxygen in carbon dioxide as they inhaled, for that matter.)

As Ravens cry points out, you're basically fighting the second law of thermodynamics here. You're trying to make a closed system inside the bag of holding (closed systems can actually exist when you've got magic), but you can't sustain one of those, on account of entropy.

So sorry, but no. Go with the necklace of adaptation (or the appropriate ioun stone) instead, if you really want to keep people inside extradimensional spaces.

[Ravens_cry]

Well, with a magic light source providing energy (like the ones already mentioned) it might be possible, though you would need to really expand the bag of holding extradimensional if your going to produce enough net oxygen for even just a halfling. It technically isn't a closed system with a light source. There must be a way to rig it so you get net oxygen, as on Starship Earth, because without it, we 02 breathing animals wouldn't survive.

NASA is doing some similar experiments, though without the bag of holding.

[kbk]

We once used a necklace of adaptation to keep a minotaur in a portable hole. We were found of saying "I choose you, minotaur of doom"

Then we forgot about him for a month, and the necklace of adaptation ran out of air.

[Sstoopidtallkid]

We once used a necklace of adaptation to keep a minotaur in a portable hole. We were found of saying "I choose you, minotaur of doom"

Then we forgot about him for a month, and the necklace of adaptation ran out of air.

There's nothing quite like being able to drop a Gelatinous Cube in your path to slow pursuers.

[Maryring]

This reminds me of the "There is a town in one of my PC's tummy" thread. That was WIN.

That... I'd like to see.

Also, you're gonna need a Decanter of Endless Water in there too, well, either that or lots of Create Water spells. Using Genesis to increase the size of the demi-plane helps a lot as well.

[Ravens_cry]

That... I'd like to see.

Also, you're gonna need a Decanter of Endless Water in there too, well, either that or lots of Create Water spells. Using Genesis to increase the size of the demi-plane helps a lot as well.

Unless you keep the bag of holding the whole time, once you have the initial water supply, (if done right) you only need to add more water at very irregular intervals.
http://en.wikipedia.org/wiki/Closed_ecological_system

[Maryring]

Yes, but you need to get some water in there to begin with.

[Bayar]

That... I'd like to see.

Also, you're gonna need a Decanter of Endless Water in there too, well, either that or lots of Create Water spells. Using Genesis to increase the size of the demi-plane helps a lot as well.

http://www.giantitp.com/forums/showthread.php?t=94358

It was actually an island. In one of the PC's tummy. And the other PC's are trying to found a city on it.

[Ravens_cry]

Yes, but you need to get some water in there to begin with.

Do rivers exist on your planet? Not everything has to be solved with magic, especially when it can be done cheaper without.

[Maryring]

Yes, you can put it in a river, but that's not half as fun as a Decanter of Endless Water.

[JeminiZero]

It might be easier if you use a bunch of everburning torches as your light source.

Once you have that, supporting the halfling may be actually be possible if you consider the following:
1) In a typical ecosystem, amount of oxygen generated is limited by the fact light comes from only one direction. So although a tree has many leaves, only the top few are most productive.
2) Light is only available half the time.

A tree in the BoH with multiple light sources from all over via many EB torches, will recieve much more net light than a typical tree in the forest. It also recieves a continuous supply of light 24 hours a day. I don't have any hard numbers, but a EB torch filled forest in a fair size BoH might be able to generate enough oxygen to support a Halfling.

[Sstoopidtallkid]

It might be easier if you use a bunch of everburning torches as your light source.

Once you have that, supporting the halfling may be actually be possible if you consider the following:
1) In a typical ecosystem, amount of oxygen generated is limited by the fact light comes from only one direction. So although a tree has many leaves, only the top few are most productive.
2) Light is only available half the time.

A tree in the BoH with multiple light sources from all over via many EB torches, will recieve much more net light than a typical tree in the forest. It also recieves a continuous supply of light 24 hours a day. I don't have any hard numbers, but a EB torch filled forest in a fair size BoH might be able to generate enough oxygen to support a Halfling.

Is a terrestial system the best option? I'd think it would be easier to balance an aquatic system.