Can Oscar Fish Hear?

A very common question we often get asked is "can fish hear?".  The answer to this question is Yes fish can hear, but not in the same way we hear sounds.  Think about it, have you ever seen a fish with ears?  Of course not, a fishes hearing isn't the same as human hearing. You can shout as loud as you like, play music at full volume, a fish will not hear anything, don't believe me?  Try the experiment yourself.

So why is this then?  Fish don't have external ears like mammals, however, they have got specialised hearing parts inside their head.  They also have an organ called the lateral line which they use to detect the tiniest vibrations in the water.   So if you were to play a radio very loudly outside the tank, the Oscar would not hear it.  On the other hand, a lot of bass as we know creates a lot of vibrations, these vibrations could be transferred through the aquarium into the water. I've never experimented myself, but I strongly suspect very heavy vibration caused by a lot of bass could well upset your fish.