On Mon, 17 Jul 95 "David Huie" <David.Huie at Bentley_COM> wrote the following
re: Yeast Explosion
> I have a problem that I'm hoping someone can give me suggestions on.
> I've had all the fish in my tank killed by acidosis...twice now. Both
> times were as a result of massive pH changes due to my inaccurate CO2
> injection method.
It sounds like this may also be due to inadequate buffering. What is your
> The first time, the tank just ran out and the pH went from 6.2 to 7.8
> in about two hours.
Hmmm ... wouldnit that be alkalosis (sorry, just being picky)
> The second time, last week the whole CO2 tank vented into the aquarium
> at once--a one inch shell of ice on the CO2 canister was a bit
> I have my CO2 canister, through a regulator, pumped into the input on
> my pump. The pump is connected to a 1/2" hosee which is connected to
> a PVC pipe with sponges inside (hanging vertically). The water is
> forced vertically down into the vertically-oriented chamber with
> sponges inside...it slows down the CO2's escape and traps some of the
> bubbles in the sponge. I think what happend was that the sponges got
> clogged with mulm and during a short power outage, with the pump
> stopped, a pressure release event like my yeast explosion
> happened--the pressure built-up behind the plugged-sponges eventually
> blew the intake off of the pump and vented the entire canister of CO2
> into my tank...the pH was something lower than 5.5 (the lowest my kit
> will measure) and all my expensive fish (including about 10 siamese
> flying foxes which cost $8 + shipping ea.) were floating uncontentedly
I'm thinking that this may be a good argument to go with a less efficient
CO2 chamber such as an upturned soda bottle bottom, so that no clogging
can really occur and you can see changes in CO2 entering the tank a bit
more easily & an overflow would just bubble out the bottom & out of the
tank fairly easily. It may cost you more in CO2 but less in fish.
> It hasn't killed any of the plants yet, but the crypts are feeling the
> strain. I haven't had any CO2 in the tank for about a week now and I
> really have to wonder what to do.
> I won't cope with another mass fish death due to massive pH
> fluxuations and I don't think I can afford a fully-automated CO2
> injection system--and I won't go back to my old unreliable yeast
> method. Isn't there a reasonably affordable reaction chamber
> available to help dissolve CO2? Even That Fish Place claimed to have
> no such thing. I had to makeshift--and it turned out to be the death
> of my fish.
The tetra diffusion chambers are something like $8 each, but maybe these
are too inefficient for you? I had no problems with pH fluctuations
using them in my 125 gal tank. I had 4 CO2 bottles running though, all
at different stages so it kept CO2 more constant than in my smaller tanks.
> I will no longer keep expensive fish because I can't afford to replace
> them. I have two 10 lb. CO2 tanks and a regulator--anything I can do
> that will make a reliable system for $100 or less?
I don't think the expense of the fish counts as much as the sensitivity
of it. Though ... I have heard/read that clown loaches are very sensitive
to nitrite, but mine survived my recent ups & downs with CO2 as did corydoras
catfish, clown pleco, kuhli loach & fancy guppies. My angelfish & fire-eel
proved to be too sensitive. I was thinking about getting some SAE's for that
tank cause it has a slight hair algae problem, but maybe I'll try oto's
instead if SAE's are too sensitive.
> Thanks in advance.
I just wanted to also let you all know that last night I accidentally turned
down the airpump on my 10 gal tank (this tank has just an UGF but is
very stable usually & was the tank I put my fish in from my problem tank
last week) ... Anyway ... this morning I noticed what I'd done & turned the
air pump back up (it powers two airstones that power the UGF) and I decided
to take some measurements even though the fish looked fine & there looked
to be no problems from my actions. The CO2 measured 45 ppm and the O2
measured about 5 ppm. Now this got me thinking that perhaps my problems
last week were not due to high CO2 but very low O2. Last week I did not
measure O2 in the tank till a few days after the high CO2 incident when
CO2 levels wer back down to normal - but even then the O2 was 5ppm. It
seems quite possible to me that the O2 was extremely low earlier & that
may have been what killed the fish & upset the N cycle.
I would like to thank everyone for their advice. I'm glad things are OK
now but I'm still trying to figure out just exactly what went wrong :-).