Had I realized this thread was here, I wouldn't have made this one about my noisy and annoying Fluval C3 which sounds more like a mini diesel engine than an aquarium filter:
Two days of FluvalC3 are enough .. Best quiet filter?
And it almost seems like it keeps getting louder
Interesting, the Tetra Advanced power filter 30-60 I bought in 2010 was almost totally silent .... until it died in July of this year (maybe because I never cleaned the impeller). I bought another one at walmart ...... vibrated like crazy ..... took it back and got another one ..... it had same defect so I got the Aqua-Tech which works fine .... the impeller noise is reasonable given the high water flow and is not annoying at all.
Also, two design flaws with Fluval:
1) You get that babbling brook sound of spashing water ...... maybe some people like the sound of the great outdoors, but I think it's ridiulous.
2) You have to break the seal to get to the impeller and it can leak. Penguin, Tetra, & Aqua-Tech impellers can be removed for easy cleaning as the entire motor is enclosed in the housing ..... thus no leaks.
Looking at Amazon reviews ....... the only thing consistent about the reviews is that they're all inconsistent and overall quality of all brands seems to be going down.
Interesting to read the Amazon review(s) about recent deteriorating quality in Penguins:
I am thinking ..... OK ...... so who has bought an HOB unit in the past six months and is happy with both their noise and filtration levels?