How does rising atmospheric CO2 affect marine organisms?

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Question:
I am seeking information on methods for enriching carbon dioxide levels in an aquarium for aquatic plants.  How can this be done?  Does it really benefit the plants?  All the information I've seen is about atmospheric carbon dioxide.

Submitted by: Greg Miller, Holcombe Grade School, Holcombe, TN

Answer:
Yes, atmospheric CO2 enrichment does benefit aquatic plants.  One of our scientific advisors, Dr. Sherwood B. Idso, has described some of his work in this area in the journal Environmental and Experimental Botany (Vol. 38, pp. 15-38, 1997).  He has generally relied on the naturally high CO2 concentrations in his home to provide his high CO2 treatments; and by sealing the tops of other aquariums with clear plastic (polyethylene) film, he has relied on the photosynthetic activities of the enclosed plants to draw down the CO2 concentrations in the airspaces above the water in those other tanks.  For really high CO2 concentrations, he has also exhaled his breath into such sealed aquariums through small lengths of aquarium air tubing he inserts into the aquariums through the plastic film that seperates them from the room air.  If you check out some aquarium supply stores and catalogues, you will additionally find that you can actually purchase equipment that will enable you to continually enrich your aquarium with CO2.