Loud Durso

[BBReef]

Does anyone know how to quiet down the air rushing into the hole at the top of the durso standpipe. ive tried a few different things, but it is just so loud. The day i installed it, it magically got quiet, but now has a tremendous amount of air rush. any tips? thanks

[reefrunner69]

Make the hole larger, just start one more size up and continue until it quiets down, I am assuming it is a hiss of inrushing air into the pipe.