How much noise is too much?

[quality_reefer]

I'm in the process of upgrading all of my equipment and I just got a really nice Koralia 450 for my 20gal. It's creating a great flow and I'm buying another one soon. I'm just a little concerned about the humming noise it makes. Could this stress the fish out? Or does it need to be an overpowering noise to cause harm?

 

[justanotherfishhead]

I wondered the same thing about loud skimmers. I guess we can't really know if they mind the noise, but they have to have clean water and good flow, so what can you do.

 

[little_fish]

I dont think the noise bothers them much, the ocean is actually pretty noisy because water carries sound better than air.