# Re: NFC: Re: Filterless Aquariums.

I still believe to approximate the displacement of h2o from an aquarium; it
would be the simplest way to weigh the materials and divide by 8.14 pounds
the weight of one gallon of water ) and subtract from the total gallons of
the tank. The formulas previously mentioned need far too much calculation. A
simple but direct route is the method of choice, at least for me. Just be
certain to use dry weight so not to calculate the saturation of the
substrate.

Lets check with the silent ones???
N E lurkers out there???

James
----- Original Message -----
From: "JLW" <JLW at pi_dune.net>
To: <nfc at actwin_com>
Sent: Sunday, February 11, 2001 9:39 PM
Subject: Re: NFC: Re: Filterless Aquariums.

> Sajjad, the correct number is 231. :)  Inches/231 = Gallons.
>
> Second, gravel/sand does NOT displace the volume of it.  There's space
> between teh grains, which is filled with water.  Figuring out the volume
> isn't easy, and differs on the type -- bigger grains, less volume per
> lb. An easy way to figure it out:  Fill a five gallon bucket with the
> desired media (smaller is okay, too) and fill it to the brim with
> water.  Pour the water carefully out into a container, and you'll get
> the ammount of the volume that is NOT gravel.  So, if you get one
> gallon, five gallons of media actually is four gallons of media.
>
> Josh.
>
> >
> > On Fri, 9 Feb 2001, Gary Rollwage wrote:
> > > How much  (on the average) does gravel, plants, etc etc. displace
> > > the amount of water in a tank?
> >
> > Hi folks,
> > Haven't read all NFC mail in a week, so, apologies if this has been
> >
> > I presume that plants would displace only a small amount of water. Even
if
> > you have a lot of plants, you aren't loosing too much of water volume.
> >
> > I also presume that stones, sand and gravel would displace the about
same
> > amount of water as their volume. Multiply the length and depth of the
tank
> > with the height of the gravel to get the volume displaced (in cubic
inches
> > of you are using inches as the measure).
> >
> > There should be a standard conversion from cubic inches to gallons which
I
> > don't know. Here is an approximate attempt: A cubic inch is equivalent
to
> > 16.4 cubic centimeters (cc) and there are 1000 cc in a liter. Assuming
> > 3.75 liters per US Gallon, we have about 3750 cc to a US Gallon or about
> > 229 cubic inches to a US Gallon.
> >
> > Assuming that you have 3" of substrate in a 55 Gallon (3x1 ft base), you
> > would then have 3 x 36 x 12 or 1296 cubic inches or about 5.6 Gallons of
> > substrate. Approximating further, each inch of substrate in a 55 Gallon
> > tank would displace about 1.5 to 2 gallons of water.
> >
> > Again, these numbers are all approximations. If anyone has better
numbers,
> > please do correct me.
> >
> > btw, does anyone have Ray Wolff's phone number (Wisconsin Rapids, WI) ?
> >
> > Tony/Ray Suydam: I got a filter from Marineland in the mail for the
AATP.
> >