Re: Water Changes Start Growth

Replying to ...

>>From: John Lobingier <jlob at wpa_net>
Date: Sun, 9 Jun 1996 17:33:25 GMT
Subject: Re:  Water Changes Start Growth

Hmmm...  Could your bubbles be this ->  I know when I make water 
changes (
with my python )  the same thing happens and not because ( IMHO ) 
anything BUT water splashing in the tank upon refill.  Even if I 
put the
python under the water so that there isn't any surface agitation 
happens.  If you watch, the python kind of "injects" air bubbles 
into the
water.  I could make this happen right now if I did a water change.

That crossed my mind John, but upon close examination, I don't 
think this is what is happening. I can see the bubbles growing from 
particular spots on the leaves before finally growing large enough 
and being released. I do water changes from a bucket, and never get 
bubbles on the glass. I'm sure that what I'm seeing is O2 due to 
photosynthesis. After the last water change I checked the pH within 
30 minutes. There was a definite downward swing. Wonder if this is 
what accounts for it? Something in my tank is buffering the water 
upward. The water I add is pH 7.0. The tank's water without CO2 
injection and sitting for a week or so is at pH 7.4 to 7.6. 30 
minutes after a water change of 20% the pH dropped down to 6.5. The 
following day moved back up to 6.8 where it seems to remain as long 
as the CO2 is being pumped into the system.

Does a sudden drop in pH make more CO2 available somehow?

Cheers, Rene