Re: [APD] Temperature, Thermometers & Mercurial Sense Perceptions

["S. Hieber" <shieber at yahoo_com>]

When you immediately sample two diff volumes of water right
next to each other, it's not hard to judge whether they are
within a few degrees of each other. And it's pretty clear
that that is plenty close enough for fish and plants. The
consistency in temperature sense perception is pretty good
over very short intervals of time.

Otoh, if you are setting the water temp at a sink that is
some distance away from the aquaria -- about 30 feet in my
case -- then temperature perception can be much farther
off. Rather than running back and forth from the aquaria to
the sink and vainly hoping that my temperature sense memory
is doing a remarkable job, I just set the faucet flow for a
specific temp, give or take a few degrees, then carry the
hose outlet to the aquaria and fill. 

Depending on the size of the hot water supply and the
amount of refill water needed, the temp can remain
reasonably constant after being set or can steadily decline
as more water enters the hot water heater. This is probably
only an issue if one is filling very many gallons of
aquarium water, ay maybe 100 or more gallons.

Of course, anyone that's ever come into the house after
spending time outside on a cold winter day, and then put
one's hands under a flow of tepid water, knows that a
human's ability to judge specific temperatures is subject
to considerable vagueness.

If I spend $50 or more each year on CO2 and maybe half that
on fish food, then considering saving two or three dollars
on a thermometer doesn't occupy much of my purchasing
decisionmaking. Alas, I am a victim of the theory of
marginal utility -- or maybe not a victim, maybe i just 
surrendered ;-) . I do not dismiss frugality as virtue, but
like yogurt, it's a matter of taste and economic
priorities.

I know longer use buckets to perform water changes because
it was just to perturbing to look into those white buckets
and wonder what color the water was ;-) .

For a similar reason, I have left off using straight pins
and their confounding head-size as measured in
angel-space-equivalents.

Completely unrelated to my pinhead thinking, I ask, how
many folks actually enjoy water changes? Is it not still
the number three least liked part of maintaining fresh
water aquaria?

Have plants, have fish, have a ball,
Scott H.
--- Raj <ggrk at blr_vsnl.net.in> wrote:

> 
> Our sense of touch is very good at comparing. When we
> try to blindly asses the temperature it can be way off.
> Once a reference is established, one can tell easily
> compare
> establishing whether the water is warmer or cooler and
> also
> to a certain degree by how much.
> 
> After some months of daily lab work I could tell quite
> accurately
> but an error could spoil my film so I always checked with
> a
> thermometer.
> 
> Raj
> 
> >If one is using no other measurement than one's sense of
> >touch, how does one know that it is accurate at
> assessing
> >temperature on any given occassion?
> >
> >Or is it just, as many of us suppose, that "accurate
> >enough" for aquatic hobby purposes is a pretty broad
> range?
> >
> >
> >sh
> >--- Raj <ggrk at blr_vsnl.net.in> wrote:
> >
> >
> > >
> > >          While developing my own slide films in the
> old
> > > days I could quite
> > > accurately tell temperature by dipping a finger in
> the
> > > water bath. Even now
> > > I compare my various tanks with touch and feel
> > > temperature assessment.
> > >
> 
> _______________________________________________
> Aquatic-Plants mailing list
> Aquatic-Plants at actwin_com
> http://www.actwin.com/mailman/listinfo/aquatic-plants
> 


Plants and DVDs for sale at the AGA table at the ACA 2005 Annual Convention, Fort Worth, Texas on July 21-24, 2005. 
ACA Convention Details at 

http://www.aca2005.org/

* * * * * * * * * * * * * * * * * * * * * *
Share the fun; show your work. 
The AGA's Sixth Annual International Aquascaping Contest is open.

Find about about here: 
http://showcase.aquatic-gardeners.org
_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo/aquatic-plants