Non caffeine thought of the day

[AJ356]

I don't consume caffeine like Magnum Man does. But one of his threads about the impact of the air from our environment on our fish got me thinking.

I have one internal filter that is missing a rubber cap at one end of the impellor, I tried to improvise on a cap I found lying around, but it's not a perfect fit. The filter is not so noisy that I find it annoying, but it got me thinking about the fish. I put my ear to the tank to get a feel for the noise and the humming sound was a lot louder than I thought it might be and got me a little concerned for the fish.

But then, I thought I'd listen to my other tanks with pretty much silent internal filters, and those tanks had almost the same level, or even the actual same level of loud humming. On the one hand, this reassured me that the noisy internal filter tank is either no louder, or barely louder than my other tanks (when putting one side of your head against the glass to listen).

I'm now figuring that tanks with internal filters are "louder" for fish than tanks with external filters? Maybe... or at least a different type of "loud"

Has anyone ever thought of the impact of noisy internal equipment on the fishes wellbeing, or perhaps there is no impact, as long the sound is continuous and doesn't startle the fish?

Perhaps it's like a human being with tinnitus?

 

[gwand]

Interesting thought. I imagine that river fish are constantly exposed to the sounds of the river as the water traverses rock formations forming varying degrees of rapids. Have you ever camped next to a stream or river? There is a relentless hum. Lake fish must have a different auditory experience.

 

[GaryE]

It's hard to understand what having a lateral line would mean, for humans since we lack that organ. It probably, maybe, could work like extra sound sensing.

I hope it's like my grandparents living with the train yards in their backyard, and barely noticing when the trains rattled through at night. I hope fish brains just cancel out the background vibrations. I had a friend who was a bass player staying with me, and you could see the fish were rattled (literally) when he practiced with even low volume.
This morning at four AM, some selfish idiot parked nearby with a giant car stereo playing the bassline of 'another one bites the dust' from Queen thumping away. It woke me up and made me remember how much I dislike that band, but I was back to sleep before the next tune.

We can't win though. Take away all those hums, and captive fish die. There can be filterless tanks, but only for a few species and only in extraordinarily low populations.

 

[Lcc86]

I often think that in terms of the spray bar on my filter, I keep it slightly above the water line and it sounds like rain, it occasionally wakes me up at night and then I wonder if it's OK for the fish? But as @GaryE says we can't take these things away!

 

[GaryE]

It was pointed out by @gwand , nature isn't quiet. I've caught aquarium fish in water so loud my friends and I had to shout, or move and lean in close to talk. A rapids isn't a silent spot, even if it's natural and far from human noises.

I've wondered about motor hums, but I think by their nature, these are sounds a brain as complex as that of a fish can filter. If I focus and listen hard, I can hear traffic on the highway about a km through the trees behind my house, but normally, I don't even know it's there. I can hear the surf from the ocean across the road, the heat pump, or the wind if I choose to, but mostly I tune that out. Sharp, crashing noises catch my ear, but chronic background noise is no problem. I expect it's the same for fish.

Fish have lateral lines - exposed nerves along their flanks that work like an ear does for us, sensing vibrations. It's why dynamite fishing kills so many - they are vulnerable to shock waves. But the organs also serve to establish the proximity of shoal mates, by sensing their movement. There has to be sound filtering going on, because in that loud rapids I mentioned above, the fish were in tight shoals as they moved through the super-oxygenated pools. They could keep formation. They had to be able to sense each other in spite of the rushing, gurgling, splashing waters.