[Prev][Next][Index]

Re: Aquatic Plants Digest V2 #35




>> It just occurred to me that the "magic" ingredient to your "Wond
>> might just be - carbon dioxide!  Some of the water sources in my
>> out of the tap saturated (maybe even supersaturated) with CO2, w
>> that rapidly rises upon standing.  The string-of-pearl bubbling 
>> that the plants are currently producing more CO2 than the water 
>> thus, you'll see more bubbling immediately after a water change,
>> water is already saturated.
>
>The pearling you see during photosynthesis is _O2_ (not CO2)  The 
>water must be at or above saturation for _oxygen_ before you will 
>see pearling. They also give off CO2, but in much smaller amounts. 
>Saturation for CO2, BTW, is high enough that everything in your 
>tank would be dead.  A useful method of euthanasia is to place a 
>sick fish in a bowl of seltzer water.

You're correct, of course. I botched that post rather badly, I'm afraid;
that last CO2 was a typo (should have been O2), but I think I had already
lost you by that point.  That's what I get for trying to quickly get out a
message while my boss is hovering about behind me.  But what do you think
about my overall theory - that the "wonder water" was supersaturated with
gases (possibly of several types - I only mentioned CO2 because I've seen
very high readings in tap water samples in my area), and that the sudden
bubbling was caused by the inability of the water to dissolve any additional
gases (again, of any type).  Thus - and this is the only important point I
was trying to make - the sudden bubbling may not have been caused by some O2
production surge, but instead by the water's inability to dissolve
additional O2.

Another possibility along this line of thought is that the water might well
continue dissolving O2, but be dumping some other gas simultaneously to
"make room".  (I'm still not wholly convinced that the "string-of-pearl"
bubbles are _always_ O2 <g>.)

The above is all based on my assumption that the maximum solubility of each
of the gases involved is limited by the presence of other gases already
dissolved - an assumption which makes sense to me, but that I don't recall
seeing addressed directly.

jim
in Sunny (for about the third time since Spring) Milwaukee