Re: NANFA-- The dissolved oxygen thang

Todd Crail (
Sun, 19 Jan 2003 18:52:22 -0500

That wouldn't suprise me if the temp played the largest role. However, I
guess my goal is to create as much DO2 as possible at any temp, esp when we
get up into the 70's and 80's over summer. I have all the equipment, has
anyone ever done a study on dissolved oxygen, or have references to papers?
I'm not real sure where to look, but I haven't put any effort forth yet
either :) I have a DO2 meter, a pH meter, and an ORP meter (oxidation redox
potential). Lots of things to watch... I can set up a control tank in the
basement just to play with the heat and whatnot (read: "Oh no honey... I'm
not putting any fish in there. This is for scientific study, I swear!" ;)

Wanna see something real crazy? Not only can O2 be limited indoors, you can
also increase the amount of CO2 composition in the air as well. Put a pH
meter on your tank that's in a room where you're entertaining a bunch of
people. Watch the pH DROP from all the excess CO2 (a weak acid) mixing into
your gas exchange. Now think about that respiration, and increased temp due
to body heat, and what a "stuffy room" really is... Wanna make it more fun?
Turn on a couple of those halogen lights that burn hot too. Oh yeah. Pale
fish in no time. Might even start gasping. People unconsciously begin
relocating in the house, or seem very uncomfortable if they can't leave. And
all this can be avoided by having a nice little line outside mixing in
atmospheric levels of O2... Well for the fish anyway. The people can just
go home if they don't like it ;)

And don't sweat it Travis. I enjoyed typing it up. I was awake anyway, and
blissfully drifted back off into sleep after I'd finished. :)

----- Original Message -----
From: "Mark" <>
To: <>
Sent: Saturday, January 18, 2003 4:09 PM
Subject: Re: NANFA-- The dissolved oxygen thang

> Wow, I never considered there might be lowered oxygen indoors. I'm kind
> surprised it would be that much of a difference. Wonder if the dissolved
> O2 levels in the tanks has anything to do with the temperature of the
> induced air. Does cold air dissolve more readily than warm air,
> of water temperature? Maybe the temperature _difference_ effects the
> dissolution of the gasses.
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