Tapping on a Fish Tank

[gypsymoth3]

why is it not a good idea to tap on a fish tank? i always thought it hurt the fish's eardrums... do they even have eardrums?... but i heard today that it can atually kill them. is this true? if so, how?

[Mr. Blue Sky]

I've tapped on many a fish tank. Most of the time the fish don't appear to notice. They don't react, at least. I seriously doubt you could kill a fish in this manner.

[Larry Mudd]

Pet store employees put those urgent little notes up because trying to keep the aquariums fingerprint-free is both wearying and futile.

[Duck Duck Goose]

Well, it's not the sound per se, it's the vibrations.

Fish in pet stores are already so stressed out that tapping on the fish tank probably doesn't faze them much, but some fish in a quieter home environment may be visibly upset by someone tapping on the tank.

Some of the more delicate and shy tropicals, like discus, may even totally freak out, bashing themselves against the sides of the tank in an attempt to escape, and may even manage to jump out of the tank.

So, generally speaking, unless it's a tank at Wal-Mart crammed full of 50-cent feeder goldfish with crazed looks, don't tap on the glass.

[Alias]

I tap lightly on my fishtank when I feed the fish. They've come to associate the sound with their food. When I tap, they come to the top and wait for their food. It doesn't seem to bother them.

[cichlidiot]

I think it's just common sense not to tap on a tank. Why do people do it? To get a reaction. If the fish flinch or dart, my experience is that it's not something the fish are enjoying. A stressed fish is more susceptible to illness. If every person that came into a store selling fish tapped on the glass, it would seem the fish wouldn't stay healthy for very long. Granted, some fish could possibly get used to this, but as DDG pointed out, I believe there's a lot of sensitive fish that probably wouldn't.

[gotpasswords]

How about I come by your house and beat on the wall with a sledge hammer? You probably wouldn't like that very much.

[Colibri]

Originally posted by gypsymoth3
i always thought it hurt the fish's eardrums... do they even have eardrums?...

Fish don't have eardrums, but sense pressure changes in water (including low frequency sound waves) with their lateral line system.

Interestingly, the cochlea of the inner ear in terrestrial vertebrates contains sensory cells similar to those in the lateral line system, and may be derived from it.

Tapping on the glass generally startles and stresses fish and should be avoided (though light taps to signal the presence of food as Alias describes is probably OK.)