Glass-Holes Overflow gurgle noise

[doubled50]

So got this 27 cube that had the glass-holes overflow installed. It makes a terrible gurgling sound from the drain pipe. The 90° elbow has a hole with a tube coming out that gurgles something fierce!

I've read to try and adjust it, but it feels like it doesn't adjust any?? Anyway I'm not sure and I'm sick of the noise. Any suggestions?

 

[doubled50]

Nevermind, it did adjust! Had to turn it. Must've been caked with salt!

 

[MMreef]

glad it worked for you

 

[RedDevil.258]

Nevermind, it did adjust! Had to turn it. Must've been caked with salt!

Yup every now and then you have to pull the rigid plastic how's out and clean the salt build up in it.