Overflow sizing

[Invigor]

from having just drilled my 105 gallon tank to handle around 3000gph thru a 2" overflow...go with 2 overflows, even with a durso the sound of the water crashing thru a 2" pipe is quite noticeable. I was debating between 1 2" hole or 2 1.5" holes, and went with the single 2" because I'm cheap. And as the case in most situations, you get what you pay for...and I didn't get quiet out of the deal.

so depending on the flow you're looking at running thru the overflow, I would recommend 2 smaller overflows over 1 large one.

another thing I noticed that helps quite a bit is for the drains, make sure the pipes aren't perfectly horizontal or vertical if you can help it. a straight drop makes for quite the crashing noise.