air exchange in terrarium

[FinnBar]

to be honest i don't think it's that important..
but i'm a little interested in the possible effects of co2 addition.. anything to keep my mind busy i guess..

[Ocelaris]

well, it's not terribly important, but plants will grow better in a higher saturation of CO2, you don't need to make a perfect environment to see the benefits of it. This is particularly true in an aquatic environment where dissolved gases are a limiting factor, but even in a greenhouse benefits can be seen. But it's a cost/benefit decision, and even as whacky technologically as I am, would not attempt such a thing. Just because for the 600$ or so to enrich a greenhouse I can think of better uses of that money... Then again If I hit the lottery tomorrow, It'd be part of the initial design of my greenhouse just to keep the mind busy...

[travelfin]

So far found ought that if my terrariums wouldn't get fresh air, the plants would be without co2 in two hours.
Also visited some friends and seen some terrariums on the net and seen the setups and the results thinking a lot of people running terrariums with too small an air exchange. They are circulating the air inside. I am doing the opposite at the cost of humidity. Just waiting to get cash to by a new camera. bouhght a Dracula two months ago now it has five new leaves. Also reading about greenhouses with air exchange once a minute to every five minutes why? And then wardian cases with only internal fans and minimum air exchange. Why?What is the reasoning behind these extremes.

[Ross]

I find this confusing. I use a thru-wall fan for air exchange only for 3 hours at night (plants consume CO2 primarily at night) and very little air exchange during daylight hours when plants normally consume O2 and produce CO2. So my theory is that with little air exchange during lights-on cycle, CO2 builds up in tank. Then at night the plants reverse and consume the CO2 they produced during day. In any case, my Dracula lotax is in bud and growing wildly, there are 4 plants in full bloom (Angraecoides) and 7 in spike. I'm not sure we are worried about anything important in the long run?

[travelfin]

Your right this is confusing, that's why I am looking for scientific proof

[Ocelaris]

Well, it depends on how densly planted the wardian case vs. terrarium is... I think Orchid tanks are very sparsely populated compared to a moss covered vivarium... I mean, when you say that the plants run out of CO2 in 2 hours, how did you determine that CO2 was the limiting factor? You would need a CO2 measuring device to really tell... There probably aren't going to be scientific experiments on as small of a scale as our small cases.

Unfortunately the best "web info" you probably will find is on the pot growing forums, I really do try and stay away from them, but there is a ton of info on CO2 etc... in that realm if you don't mind drudging through those sites.

One cheap way we used to measure CO2, which is very inexpensive is a pH sensitive vial of colored liquid... When CO2 was available, it would turn pink (acid) and when it was not, it would turn blue (basic)... because CO2 + H20 = Carbonic Acid (forget the chemical formula)

Might try sticking one of those in your tank and see if it works, only 10$. Me personally, My tank is very leaky and I just dump tons of moisture in it, so air exchange isn't a concern. Reminds me of when I was a child and my neighbor and I were discussing why trees always died in one particular spot. I guessed it was "out of nutrients" my neighbor scoffed that dirt doesn't run out of nutrients... Not that either of us was a botanical expert (turns out it was too wet), but running out of CO2 seems difficult to me to comprehend.

CO2 Indicator - ThatPetPlace.com

[snow]

i am following all this with much interest
i started a +_6 gal vivariumthe top is sealed off with saranwrap and for air i have a regular aquarium airpump running 24-7 in a small setup like this, would this good enough?