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I wondered today if my fish can sence the noise in my room. I have 2 subs and play music so loud that things sometimes fall of shelves. can my fish feel the vibrations in the water. do they like it?? how much noise can they tollerate.

Yes, fish primarily sense vibrations through their lateral line which in some species is highly sensitive.

Jim

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Water, taken in moderation, cannot hurt anybody. -- Mark Twain

yes they can feel it. they can prolly feel it better then you can because bass travels better in water then in open air. i wouldnt play it to loud. some fish are prolly more sensitive then others and they could become use to it i suppose. kinda like someone from new york living on the main street somewhere in the sticks because s/he cant sleep without the sound of traffic lol.

i wouldnt attempt to vibrate things at first. i would let them slowly get use to it over a few sessions. i have 2 twelve inch subs and a self powerd ten inch in the same room of 3 tanks but i rarely max out the system just because of the fish.

Yes they can hear it and it will stress them out. Sound moves thru water 4 times faster than thru air. The vibrations are exactly why you are not supposed to tap on the glass. You are going to have to find a solution. I lost a betta to noise. If it was the actual sound or the vibrations I couldnt say.

^_^

[hr width='40%']"Early morning, April 4
Shot rings out in the Memphis sky
Free at last, they took your life
They could not take your pride

Fish can feel vibrations better than they can hear out-of-water noises. Their ears are more tuned to the noises that fish and other underwater creatures produce, I believe. At any rate, fish in aquaria do not usually hear sounds from out of the water, because of that nice, thick glass.

On the other hand, fish are quite sensitive to vibrations. They can feel dummies tapping on the glass, they can feel loud music, they can feel people running across the floor, etc. Characins and Corydoras catfish are the fish that I've kept that seem to be extra-sensitive to vibrations; I'm sure there are more.

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And when he gets to Heaven, to Saint Peter he will tell: "One more Marine reporting, Sir! I've served my time in Hell."

yes..they do sense the vibrations coming ffrom the noise

I have to say i agree with you. I've kept the noise down to a minnimum as i added my first fish today and i don't think he'd appreciate the extra stress.

In addition to the lateral line, many fish do in fact have ears, very similar to our own. They do not have holes in the side of their head, but rather their swimbladders vibrate is response to sound waves transmitted through the water, then through their body tissues. In many regards, the swim bladder clarifies and enhances and collects the sound waves.

The swim bladder is connected to several bones which transfer the vibrations to the inner ear, and these bones vibrate the otoliths or ear stones against hair cells that generate nerve impulses.

Not too unlike our own system of hearing.

And then, many times people post and say that "noise is louder in water than in air." The question of how loud sounds are in water has bugged me for time now, simply because it is often repeated. I had a hard time believing that sounds actually get louder, I mean, there are no amplifiers in the water, so in order to look deeper into the question of how sound behaves differently in water than in air, I read the article "Viscosity Effects in Sound Waves of Finitie Amplitude" by M.J. Lighthill in the book Surveys in Mechanics published by Cambrige Univeristy Press

In Lighthill's article, there was a formula given for the diffusivity of sound, that is, the rate at which the sound will be muffled and spread out. This diffusion rate can be thought of as the rate at which the sound wave goes from peaks and valleys to a flat line.

diff of sound = kinematic viscosity*( (4/3) + (ratio of bulk to shear viscosity) + (ratio of heat capacities - 1)/(Prandtl number) )

d = v*( (4/3) + r + (g-1)/s )

d = diffusivity of sound, in m^2/s
v = the fluid's momenum diffusivity
r = ratio of bulk (or dilational) visocity to the shear vicosity of the fluid
g = ratio of the constant pressure heat capacity to the constant volume heat capacity
s = Prandtl number, the ratio of the fluid's momentum diffusivity to the fluid's heat diffusivity. Basically, s compares which diffusies faster in the medium, heat or momentum.

Anyway, I calculated these numbers for both air and water:

d_air = 5.8 * 10^-5 m^2/s
d_water = 4.8 * 10^-6 m^2/s

So you see that the sound diffusivity of air is more than 10 times that of water.
In other words, sound gets spread out and dies out more quickly in air than it does in water.

It seems to me, that sound is no louder in water than it is air, its waves remain sharper for a much longer time in water, therefore the sound does not die out nearly as quickly.

For example, someone yells at you from the end of an (American) football field, 100 yards away. If you were both underwater, it would be the same as them yelling from 10 yards away in air. Not because the person yelled any louder, but because the water keeps the sounds waves intact for a much longer time. (This is a very simple example that uses only the difference in diffusivities, there is undoubedly a difference in wavespeeds in air and water also, but 100 yards is a small enough distance and the wavespeeds so fast in both media that the difference in wavespeed error is probably small to negligible.)

Then, there is also the question of the air-water interface. Water is almost 1000 times as dense as air, and from http://www.du.edu/~jcalvert/waves/soundwav.htm "Waves from the air do not penetrate into water, and sound waves in water do not penetrate into the air. The two media are acoustically separate. This may be of interest to anglers, who can feel free to talk while they fish. They should beware of casting moving shadows on the water, however."

Basically, the density difference means that only a tiny portion of sounds from the air will be heard in the water.

So, in conclusion, sounds in water are not louder, but do not diffuse and become muffled as quickly as they do in air.