co2 in marine planted tanks

[charles matthews]

You are doing wonderful work, and I appreciate your efforts to bring marine planted tanks to a wider audience.

You didn't mention c02 supplementation in your article. I know there have been a number of threads, and some very suggestive anecdotes, regarding co2 in marine planted tanks. I wish you had addressed this in your article- it would be nice to have your sort of summary judgement as to where the "marine tank community" is in using co2 supplementation.

It has been stated that marine plants all-or almost all- freely utilize bicarbonate, and thus shouldn't need c02. However, I don't find this convincing; my large refugia max out at a pH of 8.6 or even higher by mid morning, and seem to stop there; I get markedly increased pearling with c02 infusion.

Could you please comment? Thanks again for your work; you are a very innovative aquarist!

Charles Matthews M.D.

 

[Samala]

Hi Charles! I'm so sorry to have missed this the last few days. Have you seen this article in a previous RK issue? I think it does a great job of exploring the use of free CO2, bicarbonate and other sources of carbon by photosynthetic organisms in a reef environment (or just an aquatic environment).

I didnt feel comfortable commenting on further CO2 supplementation work in the article since I still do not have bioassays to show whether or not it is detrimental to other desirable tank inhabitants (say, sessile inverts like corals). I have tried CO2 supplementation on an all macroalgae tank with good results, but have not repeated the trial. I am about to repeat it.

CO2 supplementation on seagrass tanks does veritable wonders, and macroalgae sharing their tank space (Halymenia, Ulva, Chaetomorpha, Caulerpa prolifera, Enteromorpha, Sargassum) all did very well in this environment.

The question is, of course, did they do better in this environment than in a non CO2 supplemented tank? Would they have done just as well if bicarbonates were their main source of C? Do they show a preference between the two?

I have the same questions for seagrass as well.

If only I had unlimited lab space and time I would sit down and work this all out for the next decade, easy. But its just not in the cards right now. I need help from other adventurous (and more innovative!) aquarists.

>Sarah