Re: Re: CO2 into powerhead

> From: Hardjono.Harjadi at Eng_Sun.COM (Hardjono Harjadi)
> Date: Tue, 23 May 1995 14:25:04 -0700
> Subject: Re: CO2 input into powerhead
> >
> >From: stevensj at calshp_cals.wisc.edu
> >Date: Tue, 23 May 1995 11:13:54 -0500
> >Subject: CO2 input into powerhead
> >
> >Hi everyone,
> >
> >This morning I decided to add an extra yeast + sugar CO2 bottle to my 125 gal
> >tank (I had three 1 litre bottles going but only had 7 ppm CO2).  I decided
> >to use a bigger bottle (2 litre) as suggested by someone on this list, and
> >to put the airline tubing from the bottle into the air input hole on my
> >penguin 550 powerhead (I don't normally have air going in to this).
> >Anyway ... after about 10 or 15 minutes I noticed small amounts of fine
> >bubbles coming out my powerhead & after about 30 mins the yeast + sugar
> >mixture was foaming quite a lot - this normally takes about 2 hours to
> >happen.  It is not a particularly warm day in Madison WI today (actually
> >quite cool & raining) so I can only assume that the "sucking" action of
> >the powerhead is causing the reaction to go faster.  Is this good?  It's
> >been running for over an hour yet & neither pH or CO2 concentration in 
> >the tank have changed.
> I did the same thing and I noticed that the CO2 concentration in the
> water did increase a little bit. However, the output of the powerhead was 
> still too close to the surface so I hooked up a flexible tube (the one that 
> is used for hooking up canister filter) to divert the output the powerhead 
> close to the substrate. This method increased the CO2 concentration even
> more since the CO2 stays in contact longer with the water before bubbles
> up to the surface. I like this method better than putting inverted bowl
> since I don't have to worry about Nitrogen build up.
> Hardjono
I continued to monitor the pH and CO2 during the day & the pH kept dropping
from 6.8 to 6.6 every few hours & I kept adding baking soda to get it back
up to 6.8 (I wanted to raise the KH from 2 to 4 anyway).  After the CO2
concentration reached 20 ppm I decided I did not want it to go any higher
so I moved the 2 litre bottle onto one of my tetra diffusion chambers &
put one of my old 1 litre bottles onto the powerhead (this bottle was
almost exhausted & I did not see any bubbles coming out of the powerhead
unless I gave the bottle a shake).  The CO2 stayed steady at 20 ppm last
night and was the same this morning.

So ... the moral of the story is:  CAUTION when adding extra CO2 or changing
the delivery method: monitor pH for several hours afterward & be prepared
to add baking soda if necessary.

> From: CrypDude at aol_com
> Date: Tue, 23 May 1995 19:59:41 -0400
> Subject: CO2 Reactor
> I'm not really interested in increasing the CO2's length of "submersion" by
> forcing the spray bar to spray it out at a low level in the tank--I'm more
> interested in coming up with a system (using pressure) to dissolve the CO2
> forcibly....rather than just introducing the CO2 and hoping it dissolves via
> long exposure to water (like I'm doing right now).
> If I wanted to, I could probably buy the full ORP units and hook up a
> fully-automated system to prevent such accidents, but I just can't justify
> the expense.
> I called That Fish Place--they do not sell any.  The manager there suggested
> an oxygen reactor--but it costs $120. (the cheapy cost $90) and while that
> may be efficient, I was hoping to keep it to around $50-60 tops...and have it
> be an inobtrusive component in the aquarium--not some big 18" white and blue
> canister.
> Hmmm.... your comments are appreciated.  I'm glad to know I'm not the only
> one who faces these dilemmas.
> Dave.

Dave, I suggest you try a powerhead, but read my cautions above.