loud overflow, need help
 

I am doing a freshwater test on the new setup to make sure nothing leaks, and found out the overflow is really loud. I have stockman standpipe on it, which does a good job but the noise comes from the water falling down the pipes when it hits the bend in the pipes... Does anyone have any idea how I can quite this? Thanks.
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Thing's will quiet up a little after a few weeks of having the tank running. Thing's need to get "slimed" up and you will notice a diffrence in sound.
I went through this.
Quinn also asked me the same question you did.
Yes it get's better

You also have to remember Sean that your going from having "0" noise on your current sumpless tank to having a sump so there will be a little bit of noise no matter what you do. Good thing it's not in your room :lol:

I forgot about the "sliming" effect, would it help to replace the 90degree bend with 2 45's? I figure this way it well be less of a harsh bend.

I have 2 90s in my pipe and it's almost silent. I notice you have ABS...maybe it sounds different than PVC?

hmmm maybe.... could PVC be "slicker" ?

The " slicker " is gonna come as algae coats the inside a bit ... the difference in sound between PVC and ABS would be in harmonic resonance ( thickness / density etc ) ... just wait awhile as Jonathon said and it will quiet down or use flexible tubing like I do and reduce the number of 90's that way

Cheers

I don't know that you'd find a noticable difference between ABS vs. PVC. I've got one of each on two different systems. Does that make sense ? No preferance in terms of volume...
I found that increasing the number of bends in "overflow lines" reduced noise. I also experimented with reducer bushings to slow the rate down without flooding the main tank. That's almost as controversial as a ball valve...something I wouldn't trust. Reducer bushings have a tapered edge. I believe that greatly reduces the risk of blockage.
I never heard of the "sliming" results but it sounds logical to me. Also, saltwater will have a definate sound difference compared to freshwater.
I wouldn't worry much during your "test run". (A wise move).
Experiment with different arrangements after a while.

my tank is continally getting quieter, like jon said it would. i'm using 2" pvc, and i have five 90 degree elbows, two above water, three below. i could replace them all with flexible tubing, and i may do so in the future. the canopy also helped to quiet things down. part of my problem is the fact that i have a 30" high tank, so the water is falling 3" into the overflow, then at least another five feet through the stockman into the sump. lots of water flow. be glad your tank isn't in your bedroom, because mine is, and it's not the most effective sleep aid around... :razz:

I think I might try the flexible tubing, see what that does....

for what its worth if it is loud now it will always be loud unless you change the design or move to amore sound insulating material. after a year mine has not quieted down at all because of slime build up.

Steve

you wrote:
When I set up my tank I used flexible pipe from the overflows to the sump. My tank is 6' and man it was aweful. It was ... well...flexible. It got dips that filled with water; it would fill up and then syphon...fill up and then syphon...It was not very quiet. I would really think before I did this. Finally it just fell off the overflow from all the movement.

I have ABS pipe in a similar configuration on one end of my tank...it does get quieter...Also I did not use glue so it comes apart nicely when you want to clean out the sump..

I second Ross's comments ... flex line for the drainage is not necessarily optimal. I tried that too with my first sump. If it had a low spot, then what would happen is it would slow the flow ever so slightly, then the pressure would build up and release and the flow would speed up again. It sounded like a toilet being flushed, every 30 seconds to 2 minutes. It was horrible.

The best results I've ever had with reducing noise, involved having the water "slide" into the sump at a 45 degree angle. I've tried every combination of 90 degree bend, above and below waterline, etc. etc. etc. and while some of that does work to reduce noise, for me I found the best results with a 45 degree angle. Not always easy or practical though, but something to ponder perhaps...