Bulkhead gasket/correct position?

[Cox]

I have an external overflow box and have a question concerning the correct placement of the bulkhead gasket. The gasket has a smooth side and a ribbed side. Which side should go down (against the bottom of the overflow)? I have seen these come assembled both ways so I'm not sure if it really matters?

 

[James77]

I doubt it really matters, but I have always put the ribbed part against the glass.

 

[doody]

I recently asked the same and pretty much got a similar answer. I put mine against the glass, and will be doing a water test tomarrow. So. I'll get back to you .

 

[Cox]

Cool, thanks!

 

[doody]

Well lil cox, i added water. It's been sitting for two days with no leakage. Against the glass is my advice too.