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Woll
Sun Jun 05, 2005, 01:12 AM
if plants in the wild do fine with just airation from the atmoshpere then why do we need to add extra CO2 to a tank?

Nitrogen N2 78.08%
Oxygen O2 20.95%
Water H2O 0 to 4%
Argon Ar 0.93%
Carbon Dioxide CO2 0.0360%
Neon Ne 0.0018%
Helium He 0.0005%
Methane CH4 0.00017%
Hydrogen H2 0.00005%
Nitrous Oxide N2O 0.00003%
Ozone O3 0.000004%


If water is mixed with atmospheric air in nature then only 0.036% of the total disolved gases would be CO2, if this works in nature then why the need for CO2 equipment? Wouldnt a air pump with a good air stone do just as good a job as the water will come into equalibrium with the air outside?

At 30c, CO2 can be disolved in water to a total of 66.5% (which at that level is rather toxic to most forms of life including plants (their roots need O2)).

duck
Sun Jun 05, 2005, 02:10 AM
Short answer No you don't need to add extra CO2.
Is a planted tank natural?
Has the tank the same surface area as a river, lake,ect?
Does nature keep the amount of plants hobbyist do in one area?

Some plant's grow like weeds under any condition's as algea does, some plants need certain condition's that must be met before it will grow, be it CO2,lighting ect.

goldenpigeon
Sun Jun 05, 2005, 02:17 AM
true. in the amazon river for example there is very few plants in some spots

kalebjarrod
Sun Jun 05, 2005, 06:58 AM
Unfortunatley us aquarist like to have as many plants as possible in the smallest area possible

in nature plants are held to the edges of streams etc etc

it just means they have a larger body of water to which they draw upon there co2

in nature plant material that is breaking down also produces CO2, we tend to remove all of this unsilghtly material from our tanks

there are a heap of small reason that basiclly add up too the fact that in a heavily planted aquarium if you want superb growth (not just survival) you need to add CO2 :wink: