On Wed, 24 Mar 2004 08:57:19 -0000, "Mark"
wrote:

It is often said on these NGs that the sound of the pump is small compared
to the sounds in a fishes natural environment. Being an advanced PADI scuba
diver I'm fortunate to have tested this theory out a few times and
personally I'm not convinced that this is true. Although sound underwater
travels a long way, it also decays quickly with distance. So, it is easy to
hear a boat from miles off, but it is relatively quiet until it gets close.
In fact, I'd descibe the underwater world as remarkable peaceful. I compare
this to the noise I heard when I put my ear to the fish tank and even though
the pump is quiet in the air, it sound like a pneumatic drill once my ear is
in contact with the glass and to me much louder than the fishes natural
environment - probably due to the proximity of the pump. In addition, the
sea noises are intermittent and random, unlike the constant buzz of the
pump. Now I don't want to get into a discussion about different tanks /
pumps / fish etc, I'm really thinking generically here...

1. Are the different sound volumes simply a trick of my brain (in the same
way that a room always look much brighter from the inside than the outside
because the brain "compensates")? Indeed, has anyone done any decibel
measurements to quantify this?
2. Is this constant droning harmful / torture to the fish? (I have seen it
written that "they look peaceful", but perhaps a visiting alien would
describe a man in a padded cell wearing a straitjacket as "looks peaceful"!)
I don't know how it would be measured, but again I'm interested in
scientific studies on this.

BTW, I did come across one site that had lots of info on the effects of
particular types of sounds (sonic booms, infrasound etc.) on fish, but it
was all "big scale" stuff and there was nothing on the effect on the
_constant_ buzz produced by a pump on a fish tank.

Cheers (and sorry for the long posting!)
Mark




Having grown up in SouthEast asia, I was fortunate enough to learn to
skin dive there. My first lessons was in local streams and rivers,
and later out in the ocean.

I concur with you, once you get away from the actual beach head, the
sound drops to near minimal, yes you can hear the waves hitting the
beach, the boats passing... but it is so peaceful and serene.

The rives are a little louder, but the enviroment is more closed, but
it is still sooo peaceful. At times I wish I could go back and just
float about 10 feet under the surface.

I don't really worry about it too much. I don't hang the air pump off
the tank or stand, it sits on the carpeted floor. My two HOB
Bio-Wheel's will be removed when finances allow me to get a canister,
other than that, the rooms where the tanks are located remain on the
quiter side, the nursery/childs room, and the master bedroom.

I haven't placed my ear IN the tank, but I don't hear or feel any
noise/vibrations that seem out of whack when I place my ear to the
glass.

Just my $.02.


--Tony